This is a rough layout for a conversion from 7th Sea to Spirit of the Century. The intent is to end up with something in SotC that reflects the original concept but is balanced as a SotC character, not something that's an exact replica of the original. This conversion document owes a lot to Mike Olson's Spirit of the Blank blog, although it's a lot more "traditional" take on SotC than what he's currently doing.
SotC characters have three important elements for purposes of this conversion. They are:
There's no direct equivalent of traits in SotC, but you can usually get the same flavor by raising the corresponding skills (eg, raise Finesse-related skills if you have a high Finesse). Some more specific notes:
Unlike 7th Sea, SotC has a fixed list of skills (7th Sea doesn't have one in the sense that new supplements were always creating new ones) and everyone has some level of ability in each skill, as mentioned above. Generally speaking, the best way to convert is to look at the list of SotC skills and decide what ordering they come in for you — what's your best skill, what are your second- and third-best skills, etc. You may or may not want to ignore knacks in doing this calculation: if you're basically equally good at all knacks in a skill, then you can just get the skill at a certain level in SotC and you'll be good at all the sub-parts of it (which tend to correspond to knacks). On the other hand, if you only raised one knack in a skill, you may want to take that skill at a relatively low level in SotC and then get an aspect just for that knack, like Master Lockpicker. In some cases a 7th Sea skill may not correspond to a SotC skill at all, especially for the more specialized stuff in later books; if you have something like Whaler that isn't going to come up much you're probably better off just taking it as an Aspect.
Because you have to have a level in each skill, it's easiest to just list the SotC skills on the left and what 7th Sea skills (if any) correspond to them on the right. Even if you have no corresponding skills, consider that you may still want a good value in a SotC skill if it fits the concept/mechanics. The skills are as follows (note that a few of them are replacements/additions to normal SotC skills, and the Sleight of Hand skill is removed entirely (merged into Perfom and Burglary)):
These are the most difficult to convert in the sense that they can convert to any of the three kinds of SotC things (skill, stunt, or aspect). Usually it's pretty obvious when an advantage corresponds to a skill, so we can mostly focus on the stunt/aspect tradeoff. The main differences are: aspects cost a fate point to activate whereas stunts are usually free; stunts are more specialized than aspects and can only ever apply to one skill; stunts can let you do something nobody else can whereas aspects (usually) only boost skills; and you have ten aspects but only five stunts. I think the most useful way to do it is decide if it can apply in multiple situations or to multiple skills: Large/Small, Faith, Dangerous Beauty, Sophia's Daughter, University Education. If so, it should be an aspect. On the other hand, if it's more specialized or is used more frequently or is an item or should do something other than just give +2 to a skill — Combat Reflexes, Scoundrel, Servants, Dracheneisen — it should be a stunt. Finally, languages are covered explicitly in the rules already: you know languages based on your Academics skill, and then there are Academics-related stunts to learn more.
These all just become aspects. If you have a virtue that gives a specific bonus (like, the Moon gives a bonus to perception rolls) that could convert to a stunt instead (probably an appropriate stunt off the Alertness or Investigation lists). If your nationality isn't a big part of the character you don't have to take it, but it can be useful as an aspect to represent things any Vesten would know, or traditional traits of a nation (Avalonians are stubborn, Montaignes are haughty and stylish, etc).
There are several ways to do this, but the ideal, I think, involves committing a reasonable amount of character resources but not so many that you can't do other things. Looking at the Weapon of Legend stunt for a comparison, I think a reasonable number is two stunts and one aspect. Thus:
Swordsman Schools: To belong to a school, you take one general stunt (Swordsman Training), one specific stunt (Ambrogia Training), and one aspect relating to your school (Ambrogia Apprentice, Student of <name>, Self-Taught Leegstra Swordsman). The aspect works like a normal aspect; the stunts follow this paragraph. Note that the school-specific stunts tend to grant other stunts; you can take more stunts that use these as prerequisites, but then you can't use the other stunts if you're not using the school. Also, some of the stunts technically apply to Fists — assume in this case they apply to whatever the school's weapons are. Also also, in theory you could make up more stunts to model the higher-level abilities and take those as you get more experienced. Finally, to learn a second school, it just costs one stunt and one aspect, since you already have the base stunt.
Swordsman Training [Weaponry]: Requires another school-specific stunt. This stunt gives two advantages:
Aldana Training [Weaponry]: Requires the Swordsman Training stunt and an aspect relating to this school. When using Aldana, you are considered to have the On top of It and Ready for Anything stunts.
Ambrogia Training [Weaponry]: Requires the Swordsman Training stunt and an aspect relating to this school. When using Ambrogia, you are considered to have the Dirty Fighter stunt; also, you can tag your Left-Handed aspect (if you have one) once per fight for free.
Donovan Training [Weaponry]: Requires the Swordsman Training stunt and an aspect relating to this school. Nobody ever takes this school, right? So who cares. It could perhaps give Flawless Parry and Riposte when using Donovan.
Eisenfaust Training [Weaponry]: Requires the Swordsman Training stunt and an aspect relating to this school. Another unpopular one, which could have stunts like Donovan, or perhaps Piledriver when breaking things with your Panzerhand.
Leegstra Training [Weaponry]: Requires the Swordsman Training stunt and an aspect relating to this school. When using Leegstra, you are considered to have the Crippling Blow and One Hit to the Body stunts.
Valroux Training [Weaponry]: Requires the Swordsman Training stunt and an aspect relating to this school. When using Valroux, you can make a Rapport roll to place a fragile Infuriated aspect on your opponent (which can be tagged once for free and then goes away). Actually, anyone can do that, but you can do it as a secondary action as part of an attack/defense (ie, taking a -1 to the primary roll).
Sorcery is pretty similar to swordsman schools. The main differences are that the stunts add capabilities rather than give you bonuses, and that in some cases you want to model using sorcery to aid other skills (like, Pyeryem up some cat ears to aid a listening check). Also, there's the whole half-/full-/twice-blooded thing, but I think this is easiest just not worried about: you buy however much sorcery you want to buy, and ascribe that to whatever blooding amount you want. Anyway, here are the stunts:
Sorcery [Sorcery]: This stunt means you can do some kind of sorcery, which you manage with your Sorcery skill. Just having this stunt by itself doesn't do anything, though, sorry.
Glamour [Sorcery]: Requires Sorcery. This stunt lets you take up to your Sorcery skill rank in aspects related to specific legends (Legend of Robin Goodfellow, Legend of the Green Man, etc). These aspects are applicable to any skill rolls it seems like they might be — Robin Goodfellow is applicable on any roll involving archery, Jack when outwitting people or doing tricks, etc. In addition, you can spend a fate point to get the apprentice-level effect of these legends, unless they're just some die adder (in which case you should just tag them as an aspect). You can maybe do other similar things with a Sorcery skill roll. You can spend more stunts on this to get access to more legends (probably three or four more per stunt), or to get access to the journeyman and master level abilities of the legends.
Laerdom [Sorcery]: Requires Sorcery. This sorcery sucks so it doesn't much matter, but basically this stunt lets you inscribe runes to get effects. You know one rune for every skill rank you have in Sorcery, and you roll Art (limited by Sorcery) when you want to inscribe them. Inscribing costs no fate points but you have to roll each time, and if you fail you take physical damage equal to how much you missed by. If you successfully inscribe, that creates an aspect (Rune of Styrke or whatever) that you can tag, with the first tag being free. Unlike normal aspects, however, these are tagged for +3 rather than +2, and only one rune can be tagged per roll. Instead of making an aspect, you can have the rune do whatever its other effect is, like the Fornuft rune lets you scry. Runes last for a couple rounds; if you want to make them last longer the roll is higher difficulty. You can spend more stunts on this to learn more runes (probably four or five per stunt), or to get access to the journeyman and master level abilities of the runes.
Porte [Sorcery]: Requires Sorcery. This stunt lets you blood items, sense the location of blooded items, summon blooded items, store away/retrieve items in a pocket, and catch items thrown/shot at you. These all require Sorcery rolls with various degrees of difficulty (the last one also requires an Athletics roll). You can usually reduce the difficulty of these rolls by taking more time to do them. You can blood one item per rank you have in Sorcery.
Advanced Porte [Sorcery]: Requires Porte. This stunt lets you teleport yourself and other people by walking to your blooded items. You roll Sorcery to see how long it takes you to do the walk, or maybe Resolve to resist the whispering voices.
Pyeryem [Sorcery]: Requires Sorcery. This stunt lets you take up to half your Sorcery skill (rounded up) in aspects related to animals (Cat Spirit, Wolf Spirit, Hawk Spirit, etc). These aspects are applicable to any skill roll it seems like they might be — Cat Spirit to let you move quietly or jump, for instance (when you use an aspect like this you partially transform — gaining cat ears or a tail or the like, depending on what you do). In addition, you can pay a fate point to turn into the given animal, which lasts until dawn or whatever it is. Also, you can use Sorcery to talk to animals (the difficulty is substantially lower within Ussura). You can spend more stunts on this to learn more forms (probably one or two per stunt) or to be able to transform "in spirit" without it being visible.
Sorte [Sorcery]: Requires Sorcery. This stunt lets you use the Sorcery skill to see the fate strands and arcana connected to people (this lets you use Sorcery to complement Empathy rolls, and you can use Sorcery to discover certain kinds of aspects for people). Furthermore, you can bless or curse people; this gives a +1 or -1 for all rolls associated with a particular suit (a Cups Blessing or Swords Curse). A blessing lasts until the associated roll comes up a -2 or worse; then the dice are rerolled and the blessing goes away. Similarly, a curse ends when the roll comes up +2 or better; the dice are rerolled and the curse goes away. It probably takes a Sorcery roll to place a blessing or a curse; regardless of whether the roll succeeds, the fate witch recieves a curse in that same suit herself. You can take additional stunts to make the curses more potent or longer-lasting, and to allow more complex strand manipulation (tugging, cutting, and creating).
Generally speaking you just use the SotC rules, of course. But there are a few things that seem like they should be called out specially: