In a large mixing bowl, combine the ground chicken, grated onion, beaten egg, whole-wheat breadcrumbs, salt, garlic powder, onion powder, dried parsley, black pepper, lemon juice, and olive oil; mix until evenly combined.
Divide the mixture into 4 equal portions and shape each into a patty about 1/2 inch thick.
Preheat the air fryer to 375°F (190°C) for about 5 minutes.
Lightly coat the air fryer basket with oil and arrange the patties in a single layer without overcrowding.
Cook the patties at 375°F for 10 minutes, flipping once halfway through, until the internal temperature reaches 165°F.
Let the patties rest for a few minutes before serving.