Cut chicken into bite-sized pieces. Whisk egg with salt, pepper, and garlic powder in a bowl. In another bowl, combine cornstarch and flour.
Dip chicken pieces in egg mixture, then dredge in flour and cornstarch mix until fully coated.
Preheat air fryer to 380°F. Lightly spray basket with oil. Arrange chicken in a single layer, spray tops with oil. Cook for 10–12 minutes, flipping halfway, until golden and crispy.
In a small saucepan, combine honey, soy sauce, rice vinegar, sesame oil, and cornstarch slurry. Heat over medium, stirring until thickened, about 2–3 minutes.
Transfer chicken to a bowl, pour sauce over, and toss to coat. Garnish with sesame seeds. Serve immediately with rice or veggies.