The Hollywood Reporter had a spotlight on Sony's Spider-Man films that included a nugget on Mysterio and Kraven.
This has been interpreted as Sony wanting to make solo films about Kraven and Mysterio, although the statement is a bit more vague.Other projects will focus on Kraven the Hunter and Mysterio. The idea, says a studio source, is to build out a world gradually rather than launch one immediately, as they had been trying with Spider-Man villain ensemble Sinister Six, which has been shelved.
I'm hoping these are villains Sony is thinking of using for future Spider-Man films, rather than proposed leads.