Already done:
Nora Valkyrie (RWBY)
Unlike Marvel Thor, she's actually strengthened by tasers and other electrical attacks. (I laughed so hard at Marvel Thor being taken down by a taser, the irony of that just cannot be understated.) As an added bonus, they get her hair color right.
😛 (That Thor vs Zeus ERBOH was awesome in more ways than one, and I liked that they got the detail of his hair color right, and when he references the Marvel movies Thor puts on a blond wig.
😀 Speaking of which, if the makers of that epic rap battle didn't gut struck down by lightning twice over then I guess any blasphemy against the gods is okay.
😉 )
RWBY gender flips almost everyone. For example, "Ms. Thor" (Thora?) is shipped with Lie Ren who I believe is a male character based on Mulan (I can't remember for sure). Joan of Arc because Jaune Arc, and he (who dresses as a woman at some point just as Joan dressed as a man, and he also lied his way in) and has a shipping relationship of sorts with Pyrrha who is based on Achilles (in our real world mythology, Achilles was once disguised as a girl named Pyrrha). They don't flip everyone's gender. Jaune Arc is still persecuted by a male "Cardin"al, and many faerie tale girls are still female and guys are still guys, as are some villains (and some not quite sure which side of the hero-villain line they're on). And they're also their own characters situated to that world, not like Nora is actually a goddess from Asgard (at least not that we know...)
'Course gods have been gender bending for a long, long time. There was that way too serious patch for the last 2,000 years which gender was taken way too seriously, but I think that phase is over, so - 100 BC.