To a medium non-stick skillet over medium heat, add ground beef, onion, hamburger seasoning, seasoned salt, and pepper. Cook, breaking up the beef, until no longer pink (8-10 minutes). Remove from heat and drain excess grease if necessary. Set aside.
Remove the biscuits from the can and place them on a clean work surface. Using a rolling pin, roll each biscuit to about 5-6 inches in diameter and ⅛-inch thickness.
Evenly distribute the ground beef mixture (about ¼ cup for each pie) onto one-half of each biscuit, leaving about a ¼-inch border of dough. Top each with ¼ cup shredded cheese and a tablespoon of pickles (if using).
Brush the edges of the biscuit with water. Fold the biscuit over the filling (stretching it to accommodate the filling), creating a half-moon shape. Crimp the edges together using a fork, ensuring a complete seal.
Preheat air fryer to 360°F.
Brush each hand pie with water and sprinkle each with ¼ teaspoon sesame seeds.
Spray the basket of your air fryer with nonstick cooking spray. Working in batches, place the hand pies in the basket.
Air fry at 360°F for 4 minutes. Turn over the hand pies and air fry for another 2 minutes, or until golden brown and completely cooked. Brush with melted butter.
Serve hot with ketchup and mustard.