Computer Configuration > Administrative Templates > Microsoft Edge
Both
HKLM\Software\Policies\Microsoft\Edge
OBSOLETE: This policy is obsolete and doesn't work after Microsoft Edge 84. This policy doesn't work because WebDriver is now compatible with all existing policies. This policy allows users of the WebDriver feature to override policies which can interfere with its operation. Currently this policy disables 'SitePerProcess' (Enable site isolation for every site) and 'IsolateOrigins' (Enable site isolation for specific origins) policies. If the policy is enabled, WebDriver will be able to override incomaptible policies. If the policy is disabled or not configured, WebDriver will not be allowed to override incompatible policies.