As far as I am aware it’s currently accepted practice to keep different language versions of albums in separate release groups, though there is no relationship type to link the two (or more) release groups. I made a ticket to add such a relationship and this thread to discuss whether this practice should be incorporated as a formal guideline. The release group guideline as it stands says there is no consensus on this issue, but I have had people tell me (in the context of movie soundtracks) that different language versions should have separate release groups.
EDITED BY ADMIN:
What should we do with translated versions of albums? (examples in posts below, and also soundtracks as mentioned above - for example, most Disney soundtracks get versions in different languages by different artists).
- Same release group
- Different release groups