This may be a bit premature since there is only the Book database so far, but I would recommend that credits be shared across all other databases.
Basically one credit for all the databases.
With multiple databases, it may be that the same credit would need to be created on each database. For example, The Beatles could have an About/Subject credit on Books, Posters, Comics, etc. and they would all be different.
This would make it that the same credits wouldn’t have to be created on each database or need to be linked. The credit page could be show books, posters, comic books, etc. without having to go to another database to see those items.
If using existing data from the original *ogs data, It may be require some mapping and/or duplicate removals, but in the long term would be overall better.
I remember having some discussion about this years ago, and since this is a new endeavor I thought it might be appropriate to think about it now before other databases are added.
Thank you for your consideration.