Peel and slice the onions into 1/2-inch rings. Separate the rings and set aside.
In a shallow bowl, combine flour, garlic powder, paprika, salt, and pepper.
In a second bowl, whisk the eggs until smooth.
In a third bowl, place the panko breadcrumbs.
Dip each onion ring into the flour mixture, then into the egg, then coat with breadcrumbs. Press gently to adhere.
Spray the air fryer basket with nonstick cooking spray.
Place the coated onion rings in a single layer in the basket. Lightly spray the tops with cooking spray.
Air fry at 380°F for 8–10 minutes, flipping halfway through, until golden and crispy.
Serve immediately with your favorite dipping sauce.