Although AWOP v6.01 and later versions no longer need .INI file edits in order for AWOP's NPCs to have the correct faces and skin tone, other mods may still require them.  In which case here are the edits to be made -- for performance reasons they should be avoided unless absolutely necessary:

Edit three (3) separate game .ini files ...

• FALLOUT.INI in the saved games folder
• FalloutPrefs.ini in the saved games folder
• Fallout_default.ini in the game's install folder where FalloutNV.exe is located

Change this entry in each .ini file:

bLoadFaceGenHeadEGTFiles=0

To be this instead:

bLoadFaceGenHeadEGTFiles=1

It is usually located near the bottom of the [General] section of each file, just before the [Display] section. Make sure to run the game at least once through the original game loader (i.e. by running FalloutNVlauncher.exe directly or by starting it via Steam) so that this change is applied to the game.

You may then need to also "toggle" Archive Invalidation (Off and then On again), which can be done via a Mod Manager such as Vortex, Nexus Mod Manager (NMM), Fallout Mod Manager (FOMM), or Mod Organizer (MO).

NOTE: select *only* the "clean teeth" option when installing FCO during the initial install steps for New Vegas Redesigned