Mix flour, salt, and pepper together in a shallow bowl. Press pork chops into flour mixture until coated on both sides; shake excess flour back into bowl.
Heat shortening in a large skillet over medium heat; cook pork chops until browned, about 3 minutes per side. Drain excess fat from skillet and return pork chops to skillet.
Mix 3/4 cup water, pineapple juice, sugar, lemon juice, cinnamon, and nutmeg in skillet with pork chops. Cover skillet and simmer until cooked through and sauce is somewhat reduced, about 30 minutes. Add pineapple rings and cook 5 minutes more.
Remove pork chops and pineapple from skillet. Combine 1 tablespoon water and cornstarch in a bowl; stir into sauce in the skillet until thickened. Serve sauce with pork chops and pineapple.