Preheat the air fryer to 400°F.
Cut the chicken breasts into 1-inch pieces.
Add the flour to a sealable plastic bag then add the chicken and seal the bag. Shake the bag until the chicken is coated all over.
Add the eggs to a shallow dish and whisk them until combined. Add the breadcrumbs to a second shallow dish. Remove each piece of chicken from the bag, shake off any excess flour, then dip it in the eggs then breadcrumbs. Repeat the coating process with all of the chicken pieces.
Arrange a portion of the chicken pieces in a single layer in the air fryer basket, then coat them with cooking spray.
Cook the chicken for 15 minutes, flipping them once halfway through, until they are cooked through. Repeat the cooking process with the remaining chicken pieces.