I use Jellyfin for my music collection, and sometimes the album artist and artist fields for the same artist will be populated slightly differently. For instance, I have one case where there are three different ways using &, ‘and’ and +. I have removed these from my library, updating them with manually with MusicBrainz Picard to use the same spelling, and reuploaded them to my server. However, it uses the old metadata still.
Is there a way to efficiently reset metadata for only certain albums so that these three instances are merged and I can access all three albums from the same album artist?
The server certainly should have picked up the change in metadata but I can’t help you with why it didn’t.
I can suggest that you edit the metadata in Jellyfin rather than using external tools and moving items in and out of the library. Just click the three-dot menu for a track or album and choose “Edit metadata”. If it doesn’t pick up changes made from Jellyfin then something is very wrong.