So, I've been playing a lot of Skyrim of late, and my brain invariably turned to trying to fit the FMA crew into an Elder Scrolls AU and figuring out race and... I REGRET EVERYTHING. *coughs*
Mentioned this on twitter, where Inoru (I can't remember your tumblr name, halp!! orz) asked for details, and that's easier to do without a character limit, so:
Dwemer history – and all that gold, let's be honest – reminds me a lot of Xerxes, with the advanced civilization and the vanishing without a trace, so it makes sense to me for Hoho to be Dwemer, one of the rare, improbably survivors. And, probably, he knows more about their vanishing than he lets on, the fucker. XP Because Dwemer are effectively extinct, most people who see him think he's Altmer, probably, or maybe Bosmer? I dunno. It's clear he's some race of Mer, but different people are going to notice different traits and assume different races.
(This also can sort of work '03, except he was a Dwemer and found a way to jump to a new body, some sort of Mer, and he and Dante have done this a few times, but it's stopped working so well. But I like the bhood version better, no lie.)
Probably because I'm playing Skyrim instead of Oblivion (but also because of the Dwemer connection, a bit), my brain is putting this into Skyrim, rather than Cyrodiil, which would be a far better fit for Amestris, in retrospect. But... *shrugs*
So, Trisha and the Rockbells are all Nords. Magic is so not a thing for them, though the Rockbells are maybe renowned alchemists? They probably all live near some Dwemer ruin, maybe in Markarth (altho I like the idea of them not being from Markarth, but people from Markarth totally know about them), so the Rockbells developed a skill with Dwemer technology which isn't, necessarily, unrivalled, but it's definitely known. And maybe a bit of that has to do with Pinako befriending Hoho when she was younger, and he helped he with a lot of things when he was around – he travels a lot – so she learnt a lot of the workings from him, tho she maybe doesn't realise he's actually Dwemer?
Anyway, Hoho meets Trisha during one visit, she falls madly in love, he gets talked around, they marry and have Ed and Al. And, okay, so Dwemer apparently have a sort of telepathic communication ability? (according to the wikia) And I think Hoho probably sensed a sort of connection forming with Ed, when he got old enough, and it had been a LONG FUCKING TIME and he freaked out a lot and essentially ran away (probably because he knows stuff he doesn't want his kids accidentally finding out? idk).
So, Trisha essentially raises the boys on her own, and they both look very Dwemer, and they clearly both have Dwemer talents, because they play about with magic a lot and they have that weird ability to sort of keep track of each other mentally, though neither of them really understand what they're doing, and they're both growing a lot slower than Winry, even tho she's, like, years younger than Al, because she's full-blood human and they're both part elf, and Ed really fucking hates that, but Al mostly just lets it wash off him and Winry thinks teasing Ed about it is the best thing ever.
Basically, they're family, and sometimes there's violence, but they all love each other.
And then something happens – an attack of some enemy (Reachmen? or maybe local Nords taking offence to the elf kids?) or some sort of illness sweeping through their area, and Trisha ends up dying. And no one knows how to get in contact with Hoho, except he shows up on his own a year-ish later, because Ed and Al don't know it, but they were projecting their emotions and Hoho totally heard them and eventually found his balls and came home. (Totally unlike canon, but different circumstances, okay?) He ends up talking them under his wing, and Ed is generally unimpressed, but Al's happy to have their dad back, so Ed lets it be. Hoho teaches them how to actually manage their magic and their telepathy, so they're not bumbling around, annoying the locals with candlelight spells any more (though Ed probably still does that, just because). He does, eventually, tell them that they're Dwemer, and that's what gets both boys a lot more interested in Dwemer technology – magic had been far more their interest, despite the Rockbells being very into the mechanical stuff right next door – and Ed maybe thinks exploring one of the ruins would be a lot of fun, and he talks Al into going along with, and while the automatons seemed to view them as friendly, the Falmer didn't, and Ed lost his left leg and Al was badly hurt before Hoho managed to reach them. Hoho worked with the Rockbells and they made Ed a leg out of Dwemer mechanics and he struggled – will probably always struggle with it, tbh – with it a lot, but he eventually managed to figure out how to get around on it and such, and Al doesn't move so smoothly himself any more, so they both sort of lean on each other most days.
Hoho eventually started travelling again, and while Ed and Al wanted to go with him, they couldn't really keep up with him, so they all sort of keep in contact through telepathy and Ed and Al stay in Skyrim – maybe they move to Markarth? because easier than living out in the middle of nowhere, and they can be super knowledgeable about Dwemer there, and Calcelmo and Al would probably get on really well while Ed can be super condescending and generally gets on everyone's nerves, but he knows shit – and so the boys can sort of pretend they're adventuring, a bit.
Mustang and gang, on the other hand, are all in the imperial army. Roy's probably a Breton, explaining his magic affinity, and he's really well known for his skills with fire destruction magic, but he's also scarily good at illusion magic, which he hides from most people. His aunt has a wide net of lady spies all across Tamriel, and while his direct superior knows and has been known to use that to his advantage, the upper lot don't, and Roy, at least, much prefers it that way. (He'd like it if Grumman didn't know, but he can't have everything, alas.)
Riza (and Grumman) and Maes and Gracia are all Imperials. (Likely a lot of other background cast members, too, like Maria Ross and Sheska and Denny Brosh.) The Armstrongs are probably Nords, while other state alchemists are probably Bretons or Mer (Kimblee is totally Altmer, fight me). Havoc's probably a Nord, Falman's probably Imperial, I kinda wanna say Breda's a Breton? And, lol, I sort of want to make Fuery a Khajiit, because I think that would be adorable, but he's more likely an Imperial.
I admit to being a bit torn about the Ishvalans. There's a certain sense in them being Reachmen, because that's the sort of way they're portrayed in the series, as being rather more wild and primitive, as compared to the rest of Amestris. Which feels rude and terrible and I kind of don't like that tack, so I'm leaning more toward Orsimer, because warrior tribes.
And the Xingans are totally Dunmer. Fight me.
ANYWAY. Roy, for some reason, gets posted in Skyrim, probably to help with the civil war, and he somehow meets Ed and there's drama and epic arguments and eventually they fall in love and this I don't regret. XP
I don't know that I'd want any of them to be the Dragonborn, because that would just add additional drama and I already need to not start this fic, fuck me. (If one of them was, though, it would probably be Roy, rather than Ed.) Although, lol, I also kind of like the idea of it being Riza (or Winry? she'd really hate that, omg), and the boys are just tagging along on this epic adventure, annoying the shit out of her while she's trying to save the world. XD (And now I’m really, really attracted to this idea, help. ^^; )