If you are using frozen fish, make sure you fully defrost it and REALLY pat it dry.
Get ready to dredge the fish. Add the flour, egg, and panko into their own separate bowls. Then, taking one piece of fish at a time, just go down the line.
Lightly dust the fish in flour, then coat it in the egg. Set the fish into the panko bowl and gently press the bread crumbs onto all sides of the fish. Set aside while you repeat these steps for the rest of the fillets.
Preheat your air fryer for about 5 minutes before adding the fish.
Cook at 350° for 8-10 minutes. You want it to be golden brown and crispy, and firm.