How do Character Screens work?

How would one go about creating a character screen, like the ones in Skyrim, ESO, GW2 and all other games, obviously not that advanced.

Only way I can think is have a bunch of different sets of hair for example, a few lines of code to adjust size and resolutions but keep them looking HD, and then let the players scroll and mix and match?

Could a method like this be used to create different looking AIs quickly?

There are differente ways how you could do that:

  1. always replace the entire skeletal mesh
  2. use a modular pawn
  3. morph targets -> take a look at this video from Rama
  4. tessellation:
  5. Here you can find some other ways: Character customization: how to? - Content Creation - Unreal Engine Forums