Darth Revan is technically Cannon. In Rise of Skywalker one of the groups of Sith Troopers was called Revan Legion. Thats just 1 piece of evidence hes cannon.
I think we'll get an announcement fo Galen Marek next year. I think that's why we don't get a head sculpt this time for starkiller. Even tho he didn't take his helmet off for this suit.
