You're for sure getting Starfield and Redfall gameplay trailers. You'll also get a Forza Motorsport announcement. You'll very likely get Horizon 5 DLC announcement, Hellblade 2 trailer, Plagues Tail gameplay trailer, and Perfect Dark trailer.
I doubt we see Outer World, and think there's a decent chance we see a little more of either Fable or Avowed (with the latter being a safer bet). I think Contraband, the Western game they announced, will be shown in a little more detail.
Then there's announcements from companies they work close with, or exclusives, which I expect Microsoft will announce. Some EA announcements (Fallen Order 2?), maybe something Sega related? We'll have to see.
Probably some surprises. Maybe a bit more of the Indiana Jones title Bethesda is working on? An IP revival? And a bunch of indie titles, coming to Game Pass on Day 1. And of course, some new additions to Game Pass as soon as the day of the event.
The show will most definitely be centred around the Starfield trailer, though. This game has been in development for over 10 years now, is being created by the studio known for their interactive world-creation, and is their first new IP in over 20 years. This will show how this game is attempting to be bigger, better, and more creative than any other game.
