Prep the skewers: If using wooden skewers, soak them in water for at least 15–20 minutes to prevent scorching in the air fryer.
Make the marinade: In a large bowl, whisk together olive oil, lemon juice, honey, garlic, Dijon, smoked paprika, cumin, salt, pepper, and red pepper flakes.
Marinate the chicken: Add the chicken cubes to the bowl and toss to coat. Let it sit for 15–30 minutes at room temperature, or up to 4 hours in the fridge.
Reserve 1 tablespoon of the marinade in a separate small bowl to brush during cooking.
Prep the produce: Cut the peaches, onion, and bell pepper into even pieces, about the same size as the chicken. This helps everything cook at the same rate.
Assemble the kebabs: Thread chicken, peach, onion, and bell pepper onto skewers, alternating for color and balance. Don’t pack them too tightly—leave a little space between pieces for airflow.
Preheat the air fryer: Set to 400°F (200°C) for 3–5 minutes.
Lightly spray the basket with oil to prevent sticking.
Cook the first side: Arrange kebabs in a single layer with space between them. Air fry for 7 minutes.
Flip and brush: Turn the kebabs, brush lightly with the reserved marinade, and cook for another 5–7 minutes, until the chicken reaches 165°F (74°C) and the peaches are caramelized at the edges.
Rest and garnish: Let kebabs rest for 3 minutes. Sprinkle with chopped basil or cilantro and serve with lemon wedges.
Optional glaze: For extra shine, warm 1 teaspoon honey with a squeeze of lemon and lightly brush over the peaches just before serving.