I can’t really imagine an Obi-Wan film set after ROTS without them making up any ridiculous stuff. Sonce he should have been living on Tatooine foe the entire time, I don’t think many would be interested in slice-of-life on Tatooine type of film.
They could just have the plot be about Obi-Wan protecting a settlement from criminals and/or Tusken Raiders or something.