In a shallow bowl, mix the flour, garlic powder, paprika, cumin, salt, and pepper.
In a separate bowl, beat the egg.
Place the panko breadcrumbs in another shallow bowl.
Dip each fish fillet into the flour mixture first, coating it evenly, then into the egg, and finally into the panko breadcrumbs, pressing gently to adhere.
Arrange the coated fish fillets in a single layer in the air fryer basket. You may need to do this in batches.
Air fry the fish for 10-12 minutes, flipping halfway, until they are golden brown and crispy.
While the fish cooks, warm the corn tortillas in a dry skillet or microwave until pliable.
Assemble the tacos by placing a crispy fish piece on each tortilla, followed by a generous helping of shredded cabbage, sliced avocado, and a sprinkle of fresh cilantro.
Serve immediately with lime wedges on the side for squeezing over the top.