Drain the 14.75 ounces canned flaked salmon and transfer to a large bowl; break up any large pieces with a fork.
Add 1 large egg, 5 tablespoons mayonnaise, 1 teaspoon Dijon mustard, 2 tablespoons lemon juice, 1/3 cup finely chopped onion, 3/4 cup panko breadcrumbs, 1 tablespoon chopped fresh parsley, 1 teaspoon seafood seasoning, Kosher salt to taste, and Ground black pepper to taste to the bowl.
Stir until ingredients are evenly combined. If the mixture is too dry to hold together, add a little more mayonnaise; if it is too wet, add additional panko breadcrumbs until it holds shape.
Divide the mixture into six equal portions and shape each portion into a patty about 1 inch thick.
Set the air fryer to 400°F (preheat if your air fryer recommends preheating). Lightly coat the air-fryer basket with cooking spray.
Arrange the patties in a single layer in the basket without overlapping. Lightly coat the tops of the patties with cooking spray.
Cook at 400°F for 10 to 15 minutes, flipping the patties once halfway through cooking, until the patties are golden brown and cooked through.
Remove the patties from the air fryer and serve with your preferred sauce for dipping.