PREHEAT air fryer to 400°F.
IN a food processor, chop nuts until finely chopped but not ground. Transfer to a shallow bowl or plate.
IN another shallow bowl, whisk together the 1 beaten egg, nut milk, and parsley.
DIVIDE sausage evenly into 4 portions and shape into thin, round patties (about 5 inches in diameter).
PLACE a hard-boiled egg in the center of one patty and wrap sausage around the egg, pressing and crimping to cover the entire egg. Repeat with remaining hard-boiled eggs and sausage.
DIP a sausage-covered egg into beaten egg-milk mixture, turning to cover completely, then roll in chopped nuts, pressing gently so nuts stick and completely cover the surface. Repeat with remaining eggs, egg-milk mixture, and nuts.
PLACE eggs in the air fryer basket in a single layer at least an inch apart. Cook for 14 to 15 minutes, or until nuts are golden and sausage is cooked.
SERVE with Braised Spinach and Harissa Dipping Sauce recipes below).