How to find out if external users are added in internal groups by mistake

[CSD]

Hi Team,

We have Jira and confluence in our organisation, we create separate space or projects for every customer as internal and external, we want to check if any of the user is added by mistake in any of the internal group or any other customer group by mistake, like in confluence in every space we see anonymous users, we have script which triggers and let us know that some on accidentally enabled that and saves from security breach between multiple customers?