I use Apple Music to manage my collection. I modify metadata, make playlists, and sync to devices for portable review. In Traktor, I use only the playlists under the Apple Music integration. I don't touch playlists in Traktor because they are not synced back to Apple Music. If I want to make a change to a playlist, I do it in Apple Music.
As I'm learning new songs I make changes to the Genres and Comments fields in Apple Music frequently. Unfortunately, these changes are not reflected in Traktor. According to NI, only changes to Title, Artist, Album, and Rating can be updated (https://support.native-instruments.com/hc/en-us/articles/360000777418-Changes-in-My-iTunes-Tags-Are-Not-Reflected-in-TRAKTOR).
Does anyone have a solution for forcing metadata updates to the Traktor library?