The model has 3 texture sets. Masks are used to apply dirt and blood. You can use blend color to create new combinations. You can also adjust the intensity of AO, roughness, and emissive. The color of the dirt, blood, emissive can also be changed. I recommend watching my previous video with an example of blend color.

Skins and animations video: https://youtu.be/dX9P9299dPY

Blend color example video: https://youtu.be/1bS9P8TQdG4