Season chicken pieces on all sides with 1 tsp seasoned salt and ½ tsp black pepper. Place into an oblong baking dish. Whisk together 2 ½ cups buttermilk and hot sauce, pour over chicken. Turn to coat. Chill for at least 4 hours or overnight, turning once.
Remove chicken from buttermilk, discard marinade. On a plate sift together the flour, cornstarch, 2 tsp seasoned salt, 1 tsp black pepper, garlic powder, onion powder and paprika.
In a large shallow bowl whisk together eggs, ½ tsp salt, ½ tsp black pepper, ½ cup buttermilk.
Dredge chicken pieces in flour mixture, into egg wash then into flour again. Arrange on a baking sheet. Let stand for 15 minutes to set breading.
To fry: Spray basket of air fryer liberally with cooking spray. You may also brush with oil. Preheat air fryer to 375°F for 3 minutes. (Tip: If using a parchment liner, wait to add just before chicken pieces are arranged in air fryer to prevent it from blowing around.)
Spray chicken pieces liberally on all sides with oil taking care to leave no dry flour spots. Arrange chicken in air fryer leaving space between pieces for air to circulate. Cook dark meat pieces together and breasts together, if needed. (You can also cut large breasts in half to make smaller pieces)
Cook at 375°F for 15 minutes. Gently turn pieces taking care not to disturb breading. Spray any dry spots with additional oil if needed, and continue to cook for another 10-15 minutes or until an internal temperature of 165°F is reached.
To keep chicken pieces warm between batches: Preheat oven to 200°F. Prepare a rimmed baking sheet with an oven safe baking rack. Place fried chicken on rack.
Let chicken rest 5 minutes, then serve.
Please note: Air fryers are like any other kitchen appliance, they can vary in performance. Know how your appliance performs and you'll be good to go.