She has the Bat-Bat Fruit.
Would make sense. Patrick Redfield has it in unlimited world red but Oda could bring it into canon this way.
We had batman smile in wano too ofc so a bat zoan is likely, especially a vampire model.
It reminds me of how oda didn't want shiki to have a devil fruit like that and saying he probably has to make it canon and thus shiki having it too.
Although there's still the issue of impel down staff having wings too. Which seem to be real ones? I guess they could be fake as part of the hell/demon symbolism of impel down? But hannybal was topless and had the wings? Hmm.
Idk if Oda has ever talked about this but he needs to know if he hasn't, someone needs to ask him lol.