Computer Configuration > Administrative Templates > Microsoft Edge
Both
HKLM\Software\Policies\Microsoft\Edge
This policy lets you configure the Picture in Picture floating overlay button in Microsoft Edge. The Picture in Picture floating overlay button lets user to watch videos in a floating window on top of other windows. If you enable or don't configure this policy, you can use the Picture in Picture floating overlay button in Microsoft Edge. If you disable this policy, you can't use the Picture in Picture floating overlay button in Microsoft Edge.