Preheat the air fryer to 400°F (200°C).
Place the grated potatoes and grated onion in a large bowl. Using a clean kitchen towel or cheesecloth, squeeze out as much excess moisture as possible from the mixture.
In a small bowl, combine the ground flaxseed and water. Stir well and let sit for 5 minutes to thicken, creating a flax egg.
Add the chickpea flour, flax egg, salt, black pepper, and baking powder to the grated potato and onion mixture. Mix thoroughly until well combined.
Form the mixture into 8 equal-sized patties, about 3 inches in diameter and 1/2 inch thick.
Place the latkes in a single layer in the air fryer basket. Do not overcrowd; cook in batches if necessary.
Air fry the latkes for 7 minutes. Carefully flip each latke and air fry for an additional 7 to 8 minutes, or until both sides are golden brown and crispy.
Remove the latkes from the air fryer and place on a paper towel-lined plate to absorb any excess moisture.
Serve immediately with your favorite vegan sour cream or applesauce.