How can i fix this?

Did you check https://github.com/IthanMendoza/Fresh-Moves/wiki/Fix-Black-Eyes already

Mine work for a moment, then break again. The fix doesn't work

I am having the same problem, I already set "Allow skin transparency" to "All skins" but the eyes still look like this

Looks like the brows are Z-Fighting with the iris.
I am on 1.21 with latest EMF ETF

This is the position of the eyes in my Skin.

Also, does having a "hat" affects this in any way?