If a Blade movie isn't released before Secret Wars. I think they should save him post Multiverse Saga.
Though I really want to see Wesley Snipes in Secret Wars alongside the new Blade.
I just found out he didn't get along well with Ryan Reynolds and he did something terrible to Halle Berry. So yeah I don't want to see him return anymore. And its probably unlikely anyway given his history with those actors(especially if both are in Secret Wars)
I think these are the possible characters that would appear in the big finale even if its just a cameo
Iron Man variant (RDJ)
Ironheart
War Machine
Steve Rogers variant (Chris Evans)
Sam Wilson
Bucky (I could see a Bucky variant as Captain America)
Thor
Loki
Jane as Thor
Mobius (TVA)
Hulk (Mark Ruffalo)
She-Hulk
Skaar
Dr. Strange
Nick Fury
Clint
Kate
Natasha variant (Scarlett)
Yelena
Red Guardian
The rest of Thunderbolts (whoever survives that movie)
Scarlet Witch
Quicksilver variant (either Aaron or Evan)
White Vision
Agatha Harkness
All of the 5 main Guardians
Scott Lang
Hank Pym
Janet
Hope
Cassie
Peter Parker (Tom Holland)
Dr. Strange
Clea
Wong
Son of T'Challa
Nakia
Shuri
Namor
Captain Marvel
Ms. Marvel
Photon
Binary
A couple of Eternals (I would be surprised if all of them are ignored)
Shang-Chi
Mr. Fantastic
Invisible Woman
Human Torch
Thing
Silver Surfer
Doom
Moon Knight
Werewolf by Night
Man Thing
Elsa Bloodstone
Daredevil
Echo
Blade (if they get his movie out before Secret Wars)
Tom Hardy
Tobey Maguire
Andrew Garfield
Patrick Stewart
Kelsey Grammar
Ryan Reynolds
Hugh Jackman
Several more from Fox-Men (Ian, Halle, Famke and Marsden if the recent news doesn't affect him)
Channing Tatum
Jennifer Garner
Eric Bana
Nicholas Cage (Ghost Rider)
Anyone from the previous Fox's F4 films