Prep the air fryer: Preheat to 390°F (200°C) for 3 to 5 minutes.
A hot basket helps you get a good sear right away.
Dry and season the chops: Pat pork chops dry with paper towels. In a small bowl, mix 1 tablespoon olive oil, Dijon, garlic, sage, smoked paprika, 1 teaspoon salt, and pepper. Rub all over the chops.
Let them sit while you prep the apples.
Toss the apples and onions: In a bowl, combine apple slices and onion with 1 tablespoon olive oil, maple syrup, and apple cider vinegar. Sprinkle with a pinch of salt and pepper. Toss to coat.
Start the apples: Add the apples and onion to the air fryer basket in an even layer.
Cook at 380°F (193°C) for 6 minutes, shaking halfway. They should soften slightly but still hold shape.
Add the pork chops: Scoot the apples to the sides to make room, or remove them to a plate if your basket is small. Place chops in a single layer.
Return any apples to the open spaces.
Air fry to juicy: Cook at 390°F (200°C) for 8 to 12 minutes, flipping the chops halfway. Time depends on thickness and whether bone-in or boneless. Aim for an internal temperature of 145°F (63°C).
Finish the apples: If the apples need a little more caramelization, remove the chops to rest and air fry the apples 2 more minutes.
Toss with the butter if using.
Rest and serve: Let pork rest 3 to 5 minutes. Spoon apples and onions over the top. Garnish with thyme or parsley, and serve.