Just avoid moving the opposite direction of where your opponent is hitting you. The easiest way to get this is by playing arcade mode on Very Easy. Turning up the damage and making the time limit 30 seconds also helps. On this difficulty you can just spam heavy attacks and win with pretty much any character (I prefer She-Hulk). The achievement should pop after you win the match or time runs out, but many achievements in this game are delayed so expect to wait a minute or so.
Please put any suggestions or criticisms in the comments below.