To get the metadata for artists emby has missed, go into Danilo Perez (or whichever artist) on musicbrainz, copy the last part of the url (8d0e541a-78a2-445f-a2e6-ebf20ee45f41) and paste it in the artist's edit metadata section in the musicbrainz ID.
The video sections for emby get a lot more attention (because they are more popular), but - even though I came to Emby because of video streaming at home and away - I hope they shift their focus to music for a while as I think there is a fairly large subsection of music fans looking for an option that - literally - only Roon is filling right now (and it is WAY too expensive!), classical and jazz fans.
In my opinion, as mediocre as emby is at music organization (for classical and jazz), it is better than any other server/client option I have found. Plus, with musicbrainz integration they do that the foundation to make tags easy and thorough,