Grease an 8x4-inch loaf pan with cooking spray and then dust with a little flour. Set aside.
In a bowl, blend together the flour, baking powder, baking soda, cinnamon, nutmeg and salt.
In another large-sized bowl, add oil, sugar ,applesauce, and vanilla extract and beat until well blended.
In the bowl of flour mixture, add the flour mixture and mix until just blended.
Gently fold in the zucchini, apple and walnuts.
Place the bread mixture into the prepared loaf pan evenly.
Slide the Air Fryer Basket inside and adjust the temperature to 325 °F to preheat for 5 minutes.
After preheating, arrange the loaf pan into the Air Fryer Basket.
Slide the basket into Air Fryer and set the time for 30 minutes.
After cooking time is finished, remove the loaf pan from Air Fryer and place onto a cooling rack for about 10-15 minutes.
Then turn the bread onto the cooling rack to cool completely cool before slicing.
Cut the bread into desired-sized slices and serve.