It’s not fully automated, but I use Shelfmark -> Grimmory for my ebooks. Works quite nicely with the ingestion/metadata lookup in Grimmory.

Seconding this! I’ve been quite happy with the community over at Grimmory as well as the changes. I’ve also taken a peak at BookOrbit, another fork off Booklore, which seems less resource intensive, but the metadata migration (stuff like hardcover ids, other auxiliary fields) seemed a tad more work than I wanted.