I know Jac has been pretty adamant about wanting that to be it far as Agatha All Along itself, but that's not to say she'd be opposed to incorporating those characters down the line in what could be considered a continuation of if not an outright sequel.

To "promise", though, like, I mean... I'm not totally familiar with a lot of these facts about comic book Bucky, but it can all be learned of without directly reading those comics.