Multiple ways to go about it, replace blinding sleet (imo the best option as it thematically fits all 3 specs), or it could replace glacial advance in the frost tree and just leave GA as a component of arctic assault.
It would be basically be a copy of colossus earthquaker, which imo is odd for warriors, I think it would make more sense if war shockwave had a version of Hots Thrall sundering (enhance sundering but it pushes enemies to the side with the animation).
If it replaced sleet, then swap asphyxiate with strangulate in the general tree and add a pvp talent to give blinding sleet instead of impale, or just do none of that and use it as a means of removing sleet. It wouldn’t have a stun component, just a line knockup.