How to restrict the display of the user list?

Hi, everybody,
I use nextcloud to share and manage different collaborative projects. Some of these projects are personal and other professionals and I would like to know how to prevent other users from seeing the list of users of other projects (in the contact search or in the names that appear in the drop-down menu when file sharing).
I already use the app ‘circle’ which allows to group these projects, but this does not allow to isolate users outside these groups.
I don’t know if I’m clear, and if that’s possible.
The only solution that comes to me would be to create different Nextcloud installations, but that seems absurd to me.

Thank you

JMarc

You can restrict certain features like sharing within a group, have a look into your admin page.

The best separation are indeed different setups, at a certain size this is not a bad idea, you can still share things via federated sharing. However, administrative overhead grows.

Thank you for your answer.
The idea is above all that the users between the different cannot be found.
Ideally, users should feel that the instance is only dedicated to one project.

Either I don’t yet master the different features well, or it’s not possible. And I don’t know if it’s workable.