Can I copy an Entra ID Role? No!
I did this, so you don’t have to 🙂 I’d read that it wasn’t possible, but had to see what happened out of interest!
I tried to copy the Exchange Administrator role, by taking the existing permissions of that role and squirting them into a POSH script to create a custom role.
The result: many errors like shown stating that the action is not supported on a custom role.
Below is a copy of the script showing all of the permissions that I had to remove (note all the commented permissions lines) before being able to create the role.
For reference here is a link to MSFT docs that show what you CAN set in Entra ID custom roles: User management permissions for Microsoft Entra custom roles – Microsoft Entra ID | Microsoft Learn