Seems its weird like maybe an alice flash back and a sequel ??? we have all the characters from the first movie and now also ada , barry, and Leon!
No they're clones remember.
Clones - Rain, One, Becky, and Carlos - There will possibly be several clones of each.
Non dead, original selves - Alice, Jill, Wesker, Leon, Ada, Barry, Luther and some other dude I think his name is Surgio? I think he and Luther are this movie's zombie fodder.
I've heard rumors that Claire, Chris and KMart might make cameos, but I wouldn't count on it. I would like that...but not holding my breath.