Preheat air fryer to 400 F according to manufacturer's directions.
Meanwhile, pat pork dry with paper towels. Place the pork medallions between 2 pieces of plastic wrap. Using the flat side of a meat mallet, pound medallions to 1/4-inch thickness. Remove and discard plastic wrap.
Place flour in a shallow bowl and egg in another shallow bowl. In a third shallow bowl, combine crushed potato chips, onion powder, garlic salt and black pepper. Dip pork pieces, one at a time, into flour and then into egg. Evenly coat with crumb mixture.
Lightly spray the air-fryer basket with cooking spray. Place pork pieces in a single layer in the basket. Lightly spray tops of pork pieces with cooking spray. Cook for 2 minutes. Turn pork over and lightly spray with cooking spray. Cook for 2 minutes more or until lightly golden and internal temperature of the pork reaches 145 F.
Serve pork in buns with desired condiments.