Ah, I was unsure about that. This example used the circle name as the artist for instrumental tracks: https://musicbrainz.org/release/630008c5-7ec8-4954-86b5-540e6f38f83f
I had myself as artist for the instrumentals in Bandcamp following some other tagging patterns I’d seen before, but I wasn’t sure of what the convention was here. I’ve updated it to ウタイさん (ed: seems the edits are queued).
I’m also adding work relations to the original Touhou songs. Things seem to be quite split between “Is based on” and “Is an arrangement of”. I’ve gone with the first, under the premise that the songs do not follow the song structure of the original songs (especially the first track, which includes original melodies too; the second one is closer to the original, so I’m not so sure…). Any hints there?