Have a look at this thread if your interested Corrupt Database - Transferring User Information - #72 by anon5074910. User anon5074910 is my old account so any comments in that thread are mine.
This is a more advanced backup / restore method but works, I’ve done it a few times and I know others have also. It has been a few years since I’ve done it as I never seen the need. However, I kinda overdue a clean slate.
Also, I’ve heard the Sync Your Watch State and Ratings works well but that’s not for me.
