Black spots on the bodies of the characters. (Fallout 4)

Remove the mod that did IT!!!
You can view this site what mods do!

UStanisO
Case textures.
This happens if the armor or clothes CBBE or the other, put on the vanilla body, or Vice versa.
Put the CBBE body and install replacer under that body ... And the whole business is !..

It is likely that the spots appeared on the body of a Standalone ( not CBBE ). Do you have in the game Autonomous body for YEARS?

Asking about about spots, you never said a word about the mods that you have installed.
List in the Studio, or looking for inconsistencies textures and meshes .

Black spots on the bodies of the characters
So mods in your game
As Negros are covered in soot.....

UStanisO
If you put the body SVVE or the other, else the program will need BodySlide. Well, setting a fashion for clothes/armor, carefully read the descriptions, if they fit to the body or not.