JoBlo has a source who told them that the first two spin-offs will feature popular rumor subjects Han Solo and Boba Fett. No details on Boba, but the Han film “will focus on Han and Chewy’s [sic] relationship, potentially on how they met and became partners on the Millennium Falcon.”
A Boba Fett movie is, of course, inevitable, and either Daniel Logan or Temuera Morrison could return for the role, depending on where in the timeline the story falls. Casting a young Han Solo would be significantly more of a challenge… But no doubt there are plenty of actors willing to try.
Their source also claims that the Rebels cartoon will “focus on how the rebel alliance was formed,” which doesn’t give us too much of a hint of where it fits in the intertrilogy timeline. Sure, we saw the political roots of the Rebellion begin in the cut scenes of Revenge of the Sith, but parts of the Expanded Universe imply that the Rebellion we meet in A New Hope was formed by coalition of groups working against the Empire. Not that the EU material guarantees anything, but it’s an idea with plenty of story potential to be mined.