Preheat a 6-quart air fryer to 400°F for 3 minutes. Pat chicken pieces dry, season with salt and pepper and toss with potato starch until lightly coated; shake off loose starch.
Toss gently with 1 tablespoon oil. Arrange half the chicken in a single layer in the basket, keeping pieces apart, and dab any dry starch patches with a little of the remaining oil.
Air fry for 15 to 18 minutes, turning halfway, until lightly crisp and at least 165°F in the largest pieces. Transfer to a clean plate and repeat with the remaining chicken and oil.
Meanwhile, simmer gochujang, honey, soy sauce, vinegar, water, garlic and ginger in a small saucepan for 2 to 3 minutes, stirring, until smooth and lightly thickened.
Toss both cooked batches with the warm glaze in a large bowl and serve immediately.