The issue I see with Joe's suggestion is that you can only manage LOCAL accounts like this.
I have a similar issue and I have created queries that pull out all members of the local Administrators group and I put these into a Google Sheet shared with our analysts and have them remove the accounts. I don't see how a Powershell script will help unless of course you were removing literally everything except specific accounts form the group, if you have a lot of users who have admin rights I think it would be very difficult to script the removal of the right objects.
Not a great deal of help for you but just my thoughts.