The first ever alien race is discovered. Though comparatively primitive, these aliens are advanced enough to understand and use advanced human technology with only minimal instruction after learning English. And after discovery, they emigrate from their homeworlds to the various states of the Inner Sphere and become happy productive members of their new homes. Some of them even join their new nation's armies.
These aliens of course are the Ponies of My Little Pony: Friendship is Magic. Any Xenophobic impulses are quickly allayed by the Ponies' social and friendly nature.
House Lords and Clan Khans don't even blink at their obvious non-human nature, quickly incorporating the Ponies into their militaries as they would their regular human subjects. While vehicles and mechs and the like would operate with their regular stats if they were piloted by Ponies, where Ponies would distinctively be different from their human counterparts would be in the infantry.
What kind of stats and special rules and special units would Pony Infantry have?
Edit: Assume these units are made up of standard Ponies, not Hero type Ponies or super-magical prodigies or Alicorn Princesses or whatever. Also assume similar demographics in the expatriate population, so every nation's Pony population has an even split of Earth Ponies, Pegasi, and Unicorns.