Season the chicken pieces on both sides with salt and pepper. Set aside.
In a bowl, stir together the flour and garlic powder. To a second bowl, add the eggs. In a third bowl, stir together the panko, parmesan, and Italian seasoning.
Working with 1 piece of chicken at a time, dredge the chicken in the flour, dip in the egg, then coat in the panko mixture, pressing as needed. Repeat until all of the chicken pieces are breaded. Spray the breaded chicken with nonstick cooking spray on all sides.
Place the chicken pieces in a single layer in the air fryer basket, with about 1/2 inch of space between them. Cook in the air fryer set at 375°F for 6 minutes. Flip and continue to cook for 6 minutes more.
Open the air fryer basket, and spoon about 2 tablespoons of marinara onto each piece of chicken. Top each with one mozzarella slice. Return to the air fryer, and cook until cheese is golden brown and bubbly, about 3 minutes. Top with basil.