Mix mayonnaise, garlic, lemon juice, lemon zest, salt, and pepper together in a small bowl until well combined. Set aside.
Lay artichoke hearts in a single layer on a paper towel-lined plate. Pat dry with more paper towels.
Whisk flour, water, baking powder, and salt together in a shallow dish until well combined. Mix bread crumbs, garlic powder, and paprika together in a separate shallow dish.
Dip an artichoke heart in the flour mixture until lightly coated; allow any excess to drip off. Coat in bread crumbs, then set aside on a plate. Repeat the breading process with remaining artichoke hearts.
Preheat an air fryer to 375 degrees F (190 degrees C).
Lightly spray ½ of the breaded artichoke hearts with cooking spray. Place 1 inch apart in a single layer in the air fryer basket.
Air-fry until golden and crisp, about 7 minutes, turning halfway through. Repeat to cook remaining batch.
Let stand 5 minutes after cooking to cool slightly. Serve with lemony mayo.