Computer Configuration > Administrative Templates > Microsoft Edge
Both
HKLM\Software\Policies\Microsoft\Edge
OBSOLETE: This policy is obsolete and doesn't work after Microsoft Edge 135. This policy is obsolete because we have determined that this experimental opt-out UX is not required. This policy lets you manage whether the opt-out user experience for enhanced security mode is presented when ESM is turned on for Microsoft Edge. If you enable or don't configure this policy, the UI for the opt-out user experience is on. If you disable this policy, the UI for the opt-out user experience is off. Note: If this policy is used, only the User Interface for the opt-out experience is supressed - ESM is still turned on. For more information, see the 'EnhanceSecurityMode' (Enhance the security state in Microsoft Edge) policy. For detailed information about Enhanced Security Mode, see https://go.microsoft.com/fwlink/?linkid=2185895.