Place duck breasts on a cutting board and score the duck skin, making 3-4 diagonal cuts through skin. Do not cut into the meat.
Place duck into a resealable plastic bag and add soy sauce, five-spice, mirin, honey, salt, and pepper. Mix everything together to coat duck breasts. Place in refrigerator to marinate for 24 hours.
Set the air fryer to preheat at 400°F.
When preheated, add ½ c water to bottom of the Basket. Place in duck breasts skin-side up into the Basket. Insert Probe into one of the breasts. Set Probe to 165°F. Set the cooking time to 30 minutes.
Set Probe to 125°F. for medium rare. Cook for 8 minutes flip duck breast and cook to internal temperature has reached 125°F. Let rest for 10 minutes before serving.