Preheat air fryer to 400°. In a shallow bowl, combine the first 6 ingredients. In another shallow bowl, whisk butter and sour cream. Dip chicken in butter mixture, then in crumb mixture, patting to help coating adhere., In batches, arrange chicken in a single layer on greased tray in air-fryer basket; spritz with cooking spray. Cook until coating is golden brown and chicken is no longer pink, 7-8 minutes on each side. Serve with additional sour cream and chives.