Well this movie won't have horses for either side. One, Preds riding alien horses rides in the same vein assclownery as the hounds from the last movie. Just a green alien horse with dreadlocks. You want that in the film? The previous hound design before that looked more viscous and alien, but they decided to go with the green pitbull dog thing with dreadlocks instead. I don't trust any alien equivalent companions after that. Left a sour taste in my mouth.
Two, horses went extinct in the Americas thousands of years ago. It was only the arrival of Europeans with their horses that the population was reintroduced to American soil. Since this movie takes place pre-colonialism, we won't see Comaches riding them.