I don’t think this will happen. I think Obi-wan is a more likely next spin off.
Considering they have officially announced this spin off, have directors, a writer and are currently casting Han Solo my guess would be its happening.
EDIT:
I agree with your thought about Obi Wan spinoff. I always have hated the idea of a Han Solo spinoff. We might get a Kenobi spinoff in 2020 though