The announcement of a new cast member for WandaVision spinoff Agatha: Coven of Chaos could be a big step forward for the MCU's Young Avengers.
Casting news for the WandaVision spinoff, Agatha: Coven of Chaos, bodes well for the MCU's possible Young Avengers team. In Marvel Comics, the Young Avengers are young superheroes mostly acting separately from the actual Avengers. The Marvel Cinematic Universe has been slowly introducing members of the Young Avengers, including Cassie Lang, Kate Bishop, and America Chavez. Other young characters, like Ms. Marvel and Skaar, could also join the team.
Marvel has not announced a specific movie or film for these characters to appear in together, but a team-up seems likely in the future as members of the regular MCU Avengers team continue to retire and die in action. Meanwhile, Agatha: Coven of Chaos will follow WandaVision villain and witch Agatha Harkness (Kathryn Hahn).
Details about the show are scarce, but the announcement that Heartstopper's Joe Locke has been cast in an undisclosed role suggests the show may be connected to the MCU's Young Avengers.
Not much is known about the story of Agatha: Coven of Chaos, but Agatha is likely to be seeking vengeance against Wanda. She might then target Wanda's children, Billy and Tommy. The twins are also a part of the comic book Young Avengers, known as Wiccan and Speed respectively. It hasn't been clear when or how they could be reintroduced to the MCU considering they were only an illusion in WandaVision and from an alternate timeline in Doctor Strange in the Multiverse of Madness. In the comics, Billy and Tommy are reborn to different parents. With Agatha's powers, she could also easily access a version of them. It seems likely that Locke will appear as Billy and/or Tommy. Since they weren't portrayed by identical twins as children, Locke would probably portray just one of them, most likely Billy a.k.a. Wiccan, whose powers resemble the magic of Scarlet Witch.