The body can be painted in Keel/Bright - This is a complete pack of models from Quake Live, which can be painted, including Keel
Take the body from Keel/Bright, and the head from whoever you want. If the model itself has a color, you can't change it. On sites like this one http://ws.q3df.org/model/keel/skin/pm/ , such models for different colors are usually marked as Bright. In the selection menu, they are usually shown with a white icon, or less commonly, a green one.
The xp_enemyColors command only works in the Excessive Plus mod, so you will need to figure out which command colors the body in your mod.
For example, in the OSP mod, you can color an enemy's body like this:
/color1 1111
or
/color1 2222
or
/color1 aaaa
or
/color1 iiii

pk3 files with models are universal and should work for most popular mods

If you're editing the Excessive Plus mod's .pk3 files, you shouldn't touch them. To rewrite shaders or change the .tga files, you need to:
1. Create a new empty .pk3 file. Its name must contain two z's. For example, zz-mymodel.pk3 (The point is that zz throws this file name to the end of the list, and the code from your file is read last. In this simple way, you kind of rewrite the code without touching the original code itself.)
2. You don't need to recreate everything from the excessiveplus .pk3 file. You only need to create or rewrite the small portion responsible for the changes.
3. All modified files should be in the same folders. If these folders aren't already in the .pk3 file, create them.

wrote:

yes
My goal is green pants, white shirt

?
xp_enemycolors is coded the following:12345
1 = railcolor2 = headcolor3 = shirtcolor4 = legcolor5 = second railcolor
if i remember right.