If the swai fillets are frozen, thaw them completely in the refrigerator overnight, then pat very dry with paper towels. Removing surface moisture is key to getting a nicely browned exterior in the air fryer.
Drizzle the olive oil and lemon juice over the fillets. In a small bowl, combine the garlic powder, smoked paprika, onion powder, italian seasoning, salt, and black pepper. Sprinkle the seasoning mixture evenly on both sides of each fillet.
Preheat the air fryer to 390 degrees F for 3 minutes. Lightly spray the basket with cooking spray.
Place the seasoned swai fillets in the air fryer basket in a single layer with a little space between them. Cook at 390 degrees F for 5 minutes.
Carefully flip the fillets and cook for an additional 4 to 5 minutes until the fish flakes easily with a fork and the outside has a light golden color. The internal temperature should reach 145 degrees F.
Transfer the fillets to plates, squeeze fresh lemon wedges over the top, and garnish with chopped parsley. Serve immediately with your favorite side dish.