So, I've come across this issue just today. I don't know why it happened and what could cause it. But basically, the face color differs from the neck color. As you can see on the picture, it is not a neck seam. EDIT: I have found out that it happens when I use TexBlend from CBBE with Better Females. But without Better Females and without using TexBlend, I wont be able to fix the seam perfectly. Are there any other face texture mods that can work with CBBE?