I see your point, and I agree we would probably want some metadata per revision. That will require another discussion and extra work to be scheduled. We are adding a session for next week in the rally.
FTR, there is (basic) store support to set translated metadata (and also screenshots), although translated details are not yet exposed to clients. There is a discussion going on here, Getting translated snap metadata via snapd, and there is a session scheduled for next week too. It will be great to also have input from the snapcraft team on how translations would be ideally managed from the client side (and discuss how this could affect the task being discussed here).