How do we find reserved children in an assembly before promoting it?

I am posting this question on behalf of users in my organization. When they try to move an assembly of Phy Prods to the next state, sometimes it fails as someone else might have a child locked/reserved.

What is the easiest way to find reserved/locked items in an assembly? Which widget would we need to use and which license would go with it.

According to the users, the 3DShape object seems to be reserved as well, and not just the Phy Prod.

Thanks