Remove Projects / Repos after some time

Can someone point me to a good solution on how to Archiv and then delete unused Projects / Repos after some time?

We want to run Gitlab with about 6k students, so we need to archive project/repos after 2 Years of unuse and delete them after an other two.
Is this possible out of the box atm? Any workarounds? I looked around but didn’t find any vaild solution.