Preheat the air fryer to 400°F (200°C) for 5 minutes.
Pat the whole tilapia dry with paper towels.
Rub the olive oil all over the tilapia, including inside the cavity.
In a small bowl, mix the garlic powder, paprika, salt, and black pepper.
Sprinkle the spice mixture evenly over both sides of the tilapia and inside the cavity.
Stuff the cavity of the tilapia with lemon slices and fresh parsley sprigs.
Place the tilapia in the air fryer basket, making sure it lies flat and is not overcrowded.
Cook the tilapia in the air fryer at 400°F (200°C) for 18 minutes, flipping halfway through at 9 minutes for even cooking.
Check that the fish flakes easily with a fork and the internal temperature reaches 145°F (63°C).
Carefully remove the tilapia from the air fryer and transfer to a serving plate.
Serve immediately with extra lemon wedges if desired.