Mega Abomasnow also has use as a TR attacker given its low speed, high mixed attacking stats, high attack STABs like Blizzard and Wood Hammer, good coverage, priority and a handy water and ground resist which a lot of TR teams need.
That's true; it has a lot more going for it than Crabominable (most similar mon that works on TR teams, although it's not that good) in terms of bulk and priority. The downside, of course, is that it's a mega, and Mega Mawile is by far the best Trick Room-abusing mega in OU. A good player will choose Mawile as the mega instead of Abomasnow every single time.