Question

What fighting type Pokemon are obtainable in Moon and can be used before battling Ilima?

Answer 1

Makuhita, Crabrawler, Mankey, and Machop.

If you mean before Ilima's trial, then Makuhita and Crabrawler can be found in the wild, while Machop can be traded for before his trial. Mankey and Machop in the wild can only be found after completing his trial.

Comments

Also note that you can get Pikipek/Trumbeak with Rock Smash. Not Fighting-type, but still pretty good.

Answer 2

I recommend Crabrawler, because it's like level 11 in the wild and it can be found in the berry tree
right next to the cavern. Hope I helped :D