Computer Configuration > Administrative Templates > Microsoft Edge
Both
HKLM\Software\Policies\Microsoft\Edge
Configure the list of URL patterns that specify which sites can use the clipboard site permission. Setting the policy lets you create a list of URL patterns that specify which sites can use the clipboard site permission. This doesn't include all clipboard operations on origins that match the patterns. For example, users will still be able to paste using keyboard shortcuts because this isn't controlled by the clipboard site permission. Leaving the policy unset means 'DefaultClipboardSetting' (Default clipboard site permission) applies for all sites if it's set. If it isn't set, the user's personal setting applies. For more information about valid url patterns, see https://go.microsoft.com/fwlink/?linkid=2095322. Wildcards, *, are allowed. Example value: https://www.example.com [*.]example.edu