Computer Configuration > Administrative Templates > Microsoft Edge > Content settings
Both
HKLM\Software\Policies\Microsoft\Edge
If you set this policy, you can list the URL patterns that specify which sites can ask users to grant them write access to files or directories in the host operating system's file system. If you don't set this policy, 'DefaultFileSystemWriteGuardSetting' (Control use of the File System API for writing) applies for all sites, if it's set. If not, users' personal settings apply. URL patterns can't conflict with 'FileSystemWriteBlockedForUrls' (Block write access to files and directories on these sites). Neither policy takes precedence if a URL matches with both. For detailed information about valid url patterns, see https://go.microsoft.com/fwlink/?linkid=2095322. * is not an accepted value for this policy. Example value: https://www.example.com [*.]example.edu