Encountered the same problem with infinite loading on plugin tab. An hour, and counting....Seems stuck there. (Rebooted). Just completed Blood on the Ice. Have a Hjerim house mod to enable plugin once quest was completed. Can't enable through Vortex. It was working fine yesterday. And sorry for my ignorance, but I have no idea what a "controlled folder access" is, nor where in windows defender to find that. Haven't changed any setting, etc. Later edit: still "loading". But I can get around Vortex, because that plugin shows up on my load order once game is launched.