Preheat the air fryer to 350 degrees. Cut the chicken breasts in half horizontally, pounding them to even thickness as needed then set them aside.
In a shallow bowl, combine the breadcrumbs, 6 tablespoons of Parmesan cheese, Italian seasoning, garlic powder, and salt. In a second bowl, whisk the eggs.
Dip each piece of chicken in the egg, and let the excess egg drip off the chicken. Press the chicken pieces into the breadcrumb mixture, coating them evenly.
Place the chicken in a single layer in the air fryer. Spray the tops of the chicken with an oil sprayer.
Air fry them for 8-11 minutes, flipping them halfway through the cooking time, until the chicken is golden and mostly cooked through.
Carefully spread 2 tablespoons of marinara sauce over each breast, then sprinkle with mozzarella and the remaining 2 tablespoons of Parmesan cheese. Continue cooking them for 2-3 minutes, until the cheese is melted and the chicken is cooked through to 165 degrees F.