add a category for @song instead of @cover. Artists that record with bands, solo, etc. should not have their songs listed as covers.
The @Song and @Cover tags are the same.
The site will automatically use the @Song tag if there is a relationship between the two artists on MusicBrainz.
For example, Robert Plant is a “member of” Led Zeppelin, so that‘s why his solo shows use the @Song tag.