@jonas
I'm truly confused by how it's working then.
I have these 4 artists for example. (All my files are tagged using Picard - Musicbrainz)
Using Album artist name (Album artist sort name) below. I use the Album artist name for sorting, though artist name is the same for these examples.
These 2 get sorted under S for Sammy:
Sammy Hagar (Hagar, Sammy)
Sammy Hagar & The Circle (Hagar, Sammy & Circle, The)
These 2 get sorted under H for Hagar
Sammy Hagar and the Wabos (Hagar, Sammy and the Wabos)
Sammy Hagar With Vic Johnson (Hagar, Sammy with Johnson, Vic)
There doesn't seem to be a rhyme or reason to the sorting.