Preheat your Air Fryer to 400 degrees F for 5 minutes.
Meanwhile, in a large bowl, whisk together the all-purpose flour, rice flour, baking powder, cornstarch, and kosher salt. Pour in the club soda and whisk until no large lumps remain.
Spray the preheated air fryer basket with oil spray. Dip the cauliflower florets into the batter then place them in the air fryer basket in a single layer, a fork or tongs work well for this step. Don't overcrowd the basket, work in batches if necessary!
Air fry for 12 minutes at 400 degrees F. Then carefully flip the cauliflower and cook for an additional 8 minutes. Place air fried cauliflower on a cooling rack while cooking the other batches.
In a microwave-safe bowl, combine sauce, butter, and red pepper flakes. Cook for 30–50 seconds, or until the butter is melted. Whisk to combine.
Toss the air-fried cauliflower wings in the sauce and then return them to the air fryer. Cook at 400 degrees F for an additional 2–3 minutes until the sauce has set.
Serve immediately, garnished with chopped green onion or parsley.