It's probably possible. I managed to get the nodes switched over from CentOS 8 to
Stream 8 without re-installing from scratch. It was a bit tricky, and I remember having
to manually re-populate the repos directory. I didn't have this problem with the
engine because I was already on RHEL 8. I strongly recommend you backup everything. With
the engine you can always take an engine backup, re-install a new VM, then restore the
engine from the backup. That is what I had to do when I moved over to EL8 from EL7.