Preheat your air fryer for 2-3 minutes at 400 degrees.
In a dish, measure and mix your cornmeal, flour, cheese, garlic and onion powders, cayenne, paprika, salt and pepper.
In a different dish, use a fork or a whisk to scramble up your egg and buttermilk.
Pat each catfish fillet dry with a paper towel, then dip into the egg mixture, coating both sides letting the excess drip back into the dish. A thin coating is all you need to get the crust to stick.
Press the catfish into the cornmeal mixture on both sides of fish, making sure to coat fully and evenly.
Using your tongs, carefully set your fillets evenly on the air fryer basket surface. If you wish to give a light spray of olive oil for extra crispiness and to prevent sticking, do this now.
Set your timer for 12 minutes, turning with your tongs halfway through the cooking time. At the halfway point, you can also remove from the basket to spray a small amount of lemon juice or oil to prevent it from drying out. Place back in the basket and cook the additional time.
Remove from air fryer and check to be sure that your catfish is cooked all the way through.