Is anyone aware of a tool, script or method one could use to find out whether or not a user/group has any explicit permissions over any resource on a server/domain?

Reason being, I am restructuring my groups in preparation for migrating to AD, and have many legacy groups, local and global, from way before I worked here, and which I have no clue what they are/were for.

I'm wondering if there's a way I can discover if they are referenced anywhere within my servers/domain without lengthy investigations.

Any advice/suggestions would be appreciated.

Cheers,
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