Preheat the air fryer to 400°F (200°C).
In a shallow bowl, whisk the egg. In another shallow bowl, combine Panko, Parmesan, garlic powder, oregano, salt, and pepper.
Dip each zucchini slice into the beaten egg, then coat thoroughly in the breadcrumb mixture, pressing lightly to ensure adhesion.
Arrange the zucchini in a single layer in the air fryer basket, ensuring they do not overlap. Work in batches if necessary.
Lightly spray the tops of the zucchini with cooking spray.
Cook for 8 to 10 minutes, flipping the slices halfway through the cooking time, until golden and crispy.
Remove from the air fryer and serve immediately.