I reported this problem 7 months ago, when the atlas loot link in wardrobe was showing the problem.
https://us.forums.blizzard.com/en/wow/t/cryptstalker-helm-alpha-sorting-graphical-issue/532391
It’s been this way since vanilla. I would love to see it addressed, but I’m not sure it will. 
It appears to be an alpha sorting issue, which has to do with a transparent item being displayed in front of another transparent item. In this case, the eye glow effects being in front of the transparent black shadow that darkens your character’s face under the helmet.