I am pretty sure you cannot do what you are trying to do. It may partially work with performer/composers like Leonard Bernstein and a few other living composers with large performance catalogues that roon is aware of. Those performer/composers do seem to be treated differently in certain scenarios. Maybe roon will chime in on the details. Although there is a convention in other players and a lot of public metadata that Classical composers are tagged in the album artist field roon that causes a lot of problems in roon.
There are feature requests going back years to be able to sort by composer (in the composer field) in the album view but it doesn’t seem to be straightforward:
A common workaround is to put the composer(s) into the album titles so that you can at least sort and filter on composer by album title.
