On Discogs, to avoid confusion, number are often added into brackets after an artist name.
Unfortunately, when MP3tag fetches info from Discogs, the number into brackets is taken into account.
Is it possible to get rid of it?
For example, you can see "Universe (7)" here: https://www.discogs.com/release/5214868
Because of the many artists or bands, which are named "Universe", Discogs has added ident numbers to the artist name, so one can find "Universe (1)", "Universe (2)", "Universe (3)", and so forth.
Therefore it can help for later times, to save this special Discogs artist name within a dedicated tag-field, e. g. ARTIST_DISCOGS.
Once there exist such a tag-field, one can easily remove the trailing ident number, ...
and store the clean artist name into tag-field ARTIST.
Action "Format value" ... or ... Convert "Tag-Tag":