Computer Configuration > Administrative Templates > Microsoft Edge > Content settings
Both
HKLM\Software\Policies\Microsoft\Edge
Set whether websites can display images. You can allow images on all sites ('AllowImages') or block them on all sites ('BlockImages'). If you don't configure this policy, images are allowed by default, and the user can change this setting. Policy options mapping: * AllowImages (1) = Allow all sites to show all images * BlockImages (2) = Don't allow any site to show images Use the preceding information when configuring this policy.