I've seen dumb people reset for a shiny black kyurem when you have to kill him, but if someone is wierd enough to do this, is it possible?
Unfortunately no. The only Haxorus you can catch is the single shiny one. However in both regular grass and dark grass you have a 10% chance of encountering a Fraxure, which if you catch it, will evolve into Haxorus upon leveling up.
Hope this helps