I saw a report that the writer of the Kraven movie said that Spiderman will appear in it.
It got me wondering, what if Spiderman always appears in costume, and you never see the actor? Then they can make you assume it's Tom Holland, without having him actually in the movie.
I haven't seen Infinity War yet, so I don't know exactly how it turns out, but he mentions on two separate occasions that which seems like a huge spoiler to me.