Even though Elizabeth Olsen indicated that she will not be a part of Avengers: Doomsday or Secret Wars earlier this year, it's generally assumed that she will indeed be back as Wanda Maximoff/Scarlet Witch in at least one of the upcoming MCU event movies.
Several scoopers claim to have "confirmed" Olsen's involvement, but there's been conflicting reports about when the powerful magic-wielder will make her return to the MCU.
Over the past week or so, Marvel Studios has been sharing seemingly random Scarlet Witch-related clips to social media. We did get some VisionQuest updates during NYCC earlier this month, and fans are now speculating that Olsen will show up in the series.
It's definitely a sound theory, and we recently got confirmation that VisionQuest is being marketed as the final part of a trilogy that began with WandaVision and continued in Agatha All Along, and showrunner Terry Matalas revealed that the upcoming series will "directly" connect to Marvel's first ever Disney+ series while speaking to Phase Hero.
“WandaVision is one of my most favorite things ever, watched it 3 times. So it has to be as good. It ties in directly to WandaVision.”
For what it's worth, scooper MTTSH is also claiming that Olsen will make her MCU return "sooner than you think."
Star Paul Bettany recently revealed what excited him most about VisionQuest.
“One of the things that’s fun about that is that we finally get to see what it’s like inside Vision’s mind, and it’s more cluttered than you would think. He’s clearly been saving and copying and pasting [the AIs] to keep them alive inside his head. One of them, of course, has to be kept behind a pretty impressive firewall because he’s a psychopath. But he’s a clever one.”
This "psychopath" is almost certainly James Spader's Ultron - who has been confirmed to appear in both human and robot form - but the Age of Ultron villain is far from the only AI character that'll factor into the story.
Emily Hampshire (Schitt's Creek, 12 Monkeys, The Rig) recently joined the cast as a human version of E.D.I.T.H. (Even Dead, I'm The Hero). This tech was created by Tony Stark (Robert Downey Jr.) before being passed on to Peter Parker (Tom Holland) following Iron Man's demise in Avengers: Endgame.
Kerry Condon was rumored to appear as F.R.I.D.A.Y. in human form, but we recently learned that Picard's Orla Brady will actually play the role. James D'Arcy will also be back as Edwin Jarvis in some capacity.
T’nia Miller (Foundation, The Fall of the House of Usher, La Fortuna) is set to play the Bride of Ultron, Jocasta, who is described as "cunning, powerful and driven by revenge."