Hello Tomaž Kralj
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
You can set a GPO to only redirect the default client printer into the session.
It is not possible natively to only selectively redirect USB printers but not network printers. You can also disable Printer redirection completely to avoid any printers to get redirected.
For network printers, it is usually the better approach to connect them in the session rather than redirecting them from the endpoint. This would require that the session host can reach the network printer.
Hope this helps.
If you need further help on this, tag me in a comment.
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