Preheat air fryer to 375F. In a medium mixing bowl, combine the eggs, milk, and vanilla. Whisk until smooth, then gradually add the melted butter substitute, stirring to combine.
In a separate bowl, mix all of the dry ingredients, and then make a well in the center and add the wet ingredients. If the mixture seems thick, add 1 – 2 tbsp more milk to thin it (it should be able to hold its shape when scooped).
Once the batter forms, gently fold in the apples. Be careful not to overmix because it will make the fritters tough.
Line your air fryer basket with parchment paper, leaving some room around the edges for airflow. Generously grease the parchment paper. Scoop some fritters in the basket, leaving room between them so they can spread. Spray the fritters with avocado oil spray or your preferred spray.
Air fry for 5 minutes, flip, spray once more, and then cook another 4-6 minutes or until the centers are cooked through. Work in batches as needed.
Make the glaze by whisking the lumps out of the powdered sugar, and then add 1 tbsp of water or milk at a time to reach the desired consistency. Flavor it with maple extract (if using) to taste.
Right when the fritters come out of the air fryer, use a spoon and drizzle them with glaze.