Computer Configuration > Administrative Templates > Microsoft Edge
Both
HKLM\Software\Policies\Microsoft\Edge
Allows you to set whether Enterprise Mode Site List Manager is available to users. If you enable this policy, users can see the Enterprise Mode Site List Manager nav button on edge://compat page, navigate to the tool and use it. If you disable or don't configure this policy, users won't see the Enterprise Mode Site List Manager nav button and won't be able to use it.