RTF is a global modification that replaces all towns in the game.

I didn't specify... The legs needed to be different models, a model for the left leg and a model for the right leg, but if each leg is colored with a separate texture, then everything is fine.
P.S.: I also found an interesting converter from the Heroes format to the obj format; it might also convert it back.

Okay, let's continue with the clarifications. The leg should be positioned at zero; along which axis should it be rotated?
Regarding the converter, please let me know, as I tried one, and it didn't work.

Could we create snake units based on the phoenix (but smaller) and make several of them, like ghosts (so that one unit is a swarm of snakes)? Accordingly, one of the abilities would be a chance to avoid physical damage.