Have you checked out this topic:
In general, you would only need to create an access template per role, and then assign each person to a given team with a given access template. So for 10 people, there would be 10 assignments (one time only)
Fairly soon we plan on rolling out the ability to grant access templates to multiple people at once, and we also plan on adding support to automatically assign an access template based on a person being connected with an entity, so it will be even simpler.
Going forward, you should probably limit spending time on workarounds that are predicated on multiple databases for the same type of entity, since it will be time wasted when these features are rolled out.