As a M365 Global Admin I Need to Write a Script that Can Visit All Sites

I have access to a Global Farm Admin Account on a M365 tenant. I have a script that reports all external users on all site collections that I am the owner of. The script reports errors for those sites that the admin account does not have access to.

Is there a way for me to run the script so that it will report external users on all of those site collections as well? I am will to momentarily add the Admin account to the site collections and then reverse the action.