This is based on very limited knowledge of the interworkings of Elex, but heres what I have:
There are male and female models for several armor/clothing sets, so swapping these is possible, but would swap ALL male and female models that use them, same with animations. Adding the hair models would also cause clipping issues with helmets. To my knowledge, the only player character specific model in Jax's head, so that could be swapped out. The voice could be replaced with muted audio files. So, it is doable using model swapping techniques, but it could cause a lot of unwanted side-effects.
Hope that helps.
Edited by Kyim, 07 December 2017 - 07:33 PM.