This achievement can be a bit tedious despite it only being 10 wins as the game doesn't give you much health upon defeating a new enemy. It's because of this many people tend to favor methods such as Devil Jin's laser spam by pressing Square and Triangle at the same time. Personally, I didn't have much luck with this method.
Instead, I chose Kazuya as he has many moves that can confuse the enemies. For example his Upwards + Circle + Circle + Circle +Circle which is a high kick followed by two low kicks then a medium kick. This is a fairly consistent move on the AI, however if you abuse any single move they tend to catch on. I used the X/Y away punch on occasion along with Square, Triangle, Circle X combo which is two high moves then a low and another high. By mixing up these moves along with a few cheap Square + Square combos etc I managed to do this relatively quickly.
Don't forget to block, but at the same time don't try to turtle these enemies. It feels as if the longer the fight is drawn out the better the AI becomes. Also, don't blindly attack as they'll start to catch on the more you use your go-to moves. If you start to feel nervous and the enemy turns the tide on you, pause the game and take a moment. It's a simple trick that works in most fighters or any game in general. Doing so you'll collect yourself and won't make stupid mistakes that come with playing while nervous. Good luck!