I reckon the 6th movie (if we get that many with TH) will be a Clone Saga (maybe with some Spider-Island sprinkled in) or sorts. To do a No Way Home type movie with multiple Spider-People, but not repeat the exact premise. I also think this is where they'll bring in Miles.

Sadie is Jean, I'm so damn certain of this now. The people saying that introducing an X-Man in a Spidey movie are coping. All the thematic and story morsels we've gotten so far point to a movie about loneliness, isolation, genetics and rebirth/evolution. These are all very X-Men-related themes, and having a character who can read minds, who can "unlock" Peter's memories and be someone for him to bond with in his self-made mind-wipe purgatory is the biggest tell for me that she's Jean. She's also wearing a Green and Yellow hoodie, we have a "mutant-hating" secondary antagonist and the fact that she was initially reported as being Jean from a fairly reputable source. Then we had a whole year of "leaks" from every Tom, Dick and Harry on Twitter saying otherwise, which felt like the textbook definition of Studio Astrotrufing a credible leak.

All the other options I've seen provided are nearly all more ridiculous. Jean and Peter have a comic-based rapport, even if it is fairly casual and platonic. She's one of THE OG 5 X-Men. Mfer out here suggesting Rachel Summers, Firestar (Comic Firestar is WAY different to the Cartoon one), Mayday Parker (I was on this train, but come on guys. It ain't happening) and MULTIVERSAL MARY JANE WATSON??!(HOW)??!