Prepare the Marinade: To prepare marinade, blend 1 red onion, 3 garlic cloves, and 1 tsp grated ginger in a food processor until it becomes smooth. Now, add 1/4 cup soy sauce and olive oil. Blend again at high speed until the mixture is well combined. Transfer the marinade to a large bowl. Then, stir in 1/4 cup of sweet chili sauce until evenly mixed.
Coat the Chicken: Marinate the chicken legs in the bowl. Ensure each leg is thoroughly coated with the marinade.
Preheat the Air Fryer: Preheat the air fryer to 400°F (200°C) for 5 minutes.
Cook the Chicken Legs: Place the marinated chicken legs in the air fryer basket, ensuring they are not overcrowded. Cook at 200°C (400°F) for 10-12 minutes. Use a meat thermometer to check if the internal temperature reaches at least 75°C (165°F).
Serve: Remove the chicken legs from the air fryer and let them rest for 4 minutes before serving.