How should collective pseudonyms be handled?

As long as the specific person, who is credited under the pseudonym, is known for an entry (release, recording, work) we can simply use that artist entry and enter the pseudonym as an artist credit. But there are also cases where the real artists behind the pseudonym have yet to be determined and it would be good to have a placeholder artist for them. I prefer not to use [unknown] since you can not add helpful annotations and links for the specific pseudonym credit to this entry.

Using the existing tools I have created artist entries of the type "Other" for these pseudonyms for now and added the artists which are known to have been credited under that pseudonym via "legal name" / "also performs as" relationships ("member of" rels did not seem appropriate in my cases since they did not work together). The only problem with this approach is that only the first legal name gets listed on the pseudonym artist's overview page, which gives a false impression.

So this is either a request for a specific "also performs under the pseudonym" / "pseudonym used by" artist-artist relationship (and possibly also a new artist type "(Collective) Pseudonym") or this ticket could also be turned into an MBS ticket to display all "legal name" rels of an artist (if my usage of the existing rel is correct).