Okay, so has anyone written the (possibly very depressing) Bucky/Peggy(/Steve) AU yet where Steve “dies” but Bucky doesn’t ? Like, just think of the possibilities: Bucky & Peggy bond over their mutual grief; it starts out with just wanting to get to know someone that Steve cared for, but then they realize that they’re actually becoming close friends themselves.
Bucky takes up the mantle of Cap (but struggles with it maybe, because Steve’s death isn’t made public? and he’s a lot to live up to, especially because Bucky didn’t really choose it) He helps Peggy (& co.) found S.H.I.E.L.D., but is too busy as Cap to really get involved in the politics (not that he’d want to…). And it works; Bucky in the public eye, Peggy behind the curtain. They eventually end up getting married, but it’s not a particularly happy marriage, since they’re both really in love with Steve more than they are with each other (and they both know it). (It’s honestly not very healthy for them, because both of them probably could have moved on if they had married literally anyone else.) They almost file for divorce a couple of times, but they always work through it, and eventually, there’s the children to think of (maybe? can Bucky have kids?) (And then, of course, there’s the moment when Bucky realizes he’s not aging as quickly as he should be…)
Plus, there’s all the fun consequences of the Winter Soldier never existing! (I’m sure the Russians would find someone else, but whomever they substitute won’t be anywhere near as effective as Bucky.) Moreover, it’s unlikely that Hydra would have flourished as long as it did, because Bucky’s not going to trust the man who experimented on him. At all. Bucky’ll be waiting for Zola to slip up and go back to his old ways–and before long, he does. (Or maybe he goes off on his own for a while–refusing to work with Zola–and then realizes that he should keep his enemies close.)
(And there’s so much potential for drama once they find Steve! Everyone’s a little bit jealous of Bucky because he got to live a full life with Peggy (which Steve missed out on) and he has decades more to look forward to with Steve (which Peggy will never have)). …and then Peggy dies and everything’s sad all over again ☺ )