In a large bowl, whisk all the salt, sugar and spices together, then pour in the buttermilk, whisk again and then add chicken wings and toss well to coat evenly. Set in the fridge, covered, for 1 hour, or longer if you have time.
When ready to fry, preheat the Air Fryer to 400ºF. In another large bowl, whisk together the flour and salt. Lift the wings out of the marinade, let excess drip off then dredge each wing in the flour mixture very well. Lift the wings out of the flour bowl, spray them with cooking spray and then place on the Air Fryer rack and/or grate in a single layer. Air fry for 20 minutes (or until internal temperature reaches 165º F), flipping them halfway through. Repeat frying process with remaining battered chicken.
While chicken wings are air frying, melt the butter in a small pot over medium-low heat. Add the sugar, cayenne, paprika and salt, and whisk very well until the sugar has melted. Taste, adjust for seasoning and heat, then set aside.
When ready to serve, toss the wings in batches in the butter and spice sauce and transfer to a serving bowl with the soft white bread and pickles nearby.