The two female badasses have long histories with Spidey (notably Cat, as she’s often regarded as the go-to costumed female Spider-Man character) and they are already set to hit the big screen in the Sony SpiderVerse with Silver & Black.
Right off the bat, the two most prominent possibilities that seem to come to mind with regards to casting a “femme fatale” for Spider-Man: Homecoming’s sequel are the expert thief, Black Cat and the mercenary, Silver Sable.
Recent rumors have suggested a closer continuity between the Sony Spider-Man movies and the Marvel Cinematic Universe than we had previously assumed, so this casting call could represent another step in that direction.