Preheat your air fryer to 400°F (200°C) for about 5 minutes.
In a large bowl, mix together the olive oil, garlic powder, onion powder, smoked paprika, dried oregano, salt, black pepper, and cayenne pepper (if using).
Add the chicken drumsticks to the bowl and toss them in the spice mixture until well coated. Make sure every piece is evenly seasoned.
Place the drumsticks in the air fryer basket in a single layer. Avoid overcrowding for even cooking.
Air fry the chicken drumsticks at 400°F (200°C) for 25-30 minutes, flipping halfway through, until they reach an internal temperature of 165°F (75°C) and the skin is crispy.
Once done, remove the drumsticks from the air fryer and let them rest for 5 minutes.
Garnish with freshly chopped parsley before serving.