Combine all ingredients for the marinade in a bowl and mix well. Add the paneer, red onions and bell peppers. Mix to coat on each side with the marinade. Let it rest for anywhere between 30 minutes to 24 hours in the refrigerator.
When ready to cook thread the marinated paneer, peppers, and onions in the skewers alternating between each.
Lightly grease the air fryer basket. Arrange the paneer sticks in the air fryer. Cook at 180 degrees or 360F for 5 minutes.
Turn the paneer sticks and cook for 5 more minutes, then serve.