Currently when an artist is credited on a relationship they do not have a credit specific sort name. But MB API could use a sort name of an matching alias if it exists.

Take e.g. the composer on

https://musicbrainz.org/ws/2/release/8f2454e1-4e68-4500-beff-8501846595bf?inc=aliases+artist-credits+recordings+recording-level-rels+work-level-rels+work-rels+artist-rels&fmt=json

The composer of the tracks is the artist Fasme. The target-credit is "Tom Ferreira". There is also a legal-name alias for "Tom Ferreira" on the artist, with a sortname of "Ferreira, Tom".

Hence the webservice could return a field "target-credit-sort-name" set to "Ferreira, Tom". If there is no such alias "target-credit-sort-name" should be null or not set at all.

This would help implementing poper sortnames for artist credits in Picard as requested at PICARD-2197