Preheat your air fryer to 380°F (190°C).
Pat the cod fillets completely dry with paper towels, then season both sides lightly with salt, pepper, and the smoked paprika.
In a shallow dish or wide bowl, whisk together the panko breadcrumbs, garlic powder, and dried parsley. Drizzle the olive oil over the mixture and stir well until the breadcrumbs are lightly moistened.
Brush the Dijon mustard (or mayonnaise) evenly over the top and sides of each cod fillet.
Press the mustard-coated side of the cod firmly into the panko mixture so the breadcrumbs stick and form an even crust.
Place the breaded cod fillets in a single layer in the air fryer basket, ensuring they do not overlap.
Air fry for 10-12 minutes, or until the panko is golden brown and the fish flakes easily with a fork (internal temperature should reach 145°F).
Serve immediately with fresh lemon wedges.