Preheat a 6-quart or larger air fryer to 390°F for 5 minutes.
Prick potatoes all over (about 16 times) with a fork.
Rub the potatoes evenly with oil; sprinkle all over with pepper and salt.
Arrange the potatoes about 1 inch apart in the air-fryer basket.
Cook until the potatoes are fork-tender and the skins are golden brown and crisp, about 50 minutes.
Let stand for 5 minutes.
Slice in half lengthwise.
If desired, serve with sour cream (or yogurt) and garnish with chives.
