Honestly, re: canonblindness-- the only thing you really need to know is that Flint lost his 'Steve' and basically turned himself into the Winter Soldier through sheer force of anger and will. If the parallels help, haha.

I'd be up for trying it, absolutely! Flint is honestly going to be a pretty mellow mass murderer, all things considered, because he's away from the Dumpster Fire that is Nassau and all his horrible machinations but if you'd like to engineer some Clash of the Titans esque CR we can always have them meet in a crisis and Flint can go all Do As I Say Or Else on him, which... I imagine Bucky might not take too well, given his history. Thoughts?