Nuka world adds several hair dyes to the game, which are set up to be fully playable. However, for some reason those hair dyes are not actually added to the list of playable hairstyles and colors. Normally, this should be considered cut content rather than a bug. However, a search on the subject seems to indicate that these hair dyes were well known and used when Nuka World launched as a DLC, and may indicate that at some point a change to the game rendered them inaccessible.
I have posted a mod that makes them inaccessible on PC, and per usual the permissions are fully open for inclusion if the UFO4P team opts to address this. The mod I posted works via script injection, which functions for PC and Xbox. For Playstation users, this fix could be accomplished by directly editing the "ChargenOptionsSortList" FormList.