Timeline wise, I could see a sequel, but for those two characters to reappear in Episode 9 (thus to have been around, but not appeared at all, during the events of Episodes 4,5,6,7 and 8) seems a bit hard to swallow. Qi'ra is human, I guess, so she'd also be really OLD.
All about right IMO.
Surprised how they ended it though - I thought (perhaps naively) that the idea of the spin-off movies was that they would be individual / self-contained stories, yet the ending to this one - Han's girl going off to meet / join forces with Maul, was absolutely set up for a...