The default behavior for beets when having two CDs/vinyls for an album is to copy everything in a folder and tracks are numbered in continuation to the first CD.
I’d like to have it like it should be (in my opinion): separate folders for each CD: like CD1, CD2.
One example: DJ Shadow - Our Pathetic Age. The album has two CDs - one instrumental and one with vocals. Another one: Opeth - In Cauda Venenum - one CD with English lyrics/vocals, one with Swedish lyrics/vocals.