Preheat an air fryer to 375 degrees F (190 degrees C) according to manufacturer's instructions. Lay out a sheet of parchment or waxed paper.

Place thawed potatoes and shredded onion on several layers of paper towels. Cover with more paper towels and press to squeeze out most of the liquid.

Whisk together egg, salt, and pepper in a large bowl. Stir in potatoes and onion with a fork. Sprinkle matzo meal on top and stir until ingredients are evenly distributed. Use your hands to form mixture into ten 3- to 4-inch wide patties. Place patties on the parchment or waxed paper.

Spray the air fryer basket with cooking spray. Carefully place half of the patties in the basket and spray generously with cooking spray.

Air-fry until crispy and dark golden brown on the outside, 10 to 12 minutes. (Check for doneness at 8 minutes if you prefer a softer latke.) Remove latkes to a plate. Repeat with remaining patties, spraying them with cooking spray before cooking.