The Israeli rights society ACUM has a concept of works who have different versions.
Basically, ACUM works map to MB works and versions to a recording or arrangement.
For example: Song “ערב של שושנים” - MusicBrainz, has 185 versions in ACUM: https://nocs.acum.org.il/acumsitesearchdb/work?workid=1028517, with 16 different ISWCs.
Currently the ACUM ID used in works is the version ID because that what appears in ISWCNet. For example ISWC T-002.059.733-4 is linked in ISWCNet to ACUM IDs 1028517001, 1028517134 and 1028517115.
As far as I know, ACUM version IDs are simply the work ID + 3 digit index.
There is a possibility that one ACUM work would map to more than one MB work (e.g. classical music arrangements which I know nothing about). In this case we can maybe manually set the ACUM ID to the different version IDs.
I suggest using ACUM work ID instead of version ID.
What do you think?