If they mangle it, they can pretty much put any non-male derivative heroine out there (e.g. Batgirl no, Widow yes).
If you want a real superheroine (and no one really does, it seems, hence all the black leather), then Wonder Woman is a lock. But done right, a la the Carter series.
I guess they could do something with Scarlet Witch. Not sure what. She's never stood on her own much. And she couldn't very well be Scarlet Witch in black leather.
Otherwise, it's gotta be La Femme Natasha.