Rinse fish thoroughly in cold water, and pat dry. Place fish in an aluminum foil-lined shallow baking pan.
Sauté onion, green pepper, garlic, parsley, and celery in shortening in a large skillet until tender. Add shrimp, oysters, bay leaf, and seasonings; cook over medium heat, stirring constantly, 5 minutes or until shrimp turns pink. Discard bay leaf. Stir in bread cubes.
Place stuffing in fish cavity; secure with skewers or wooden picks. Pour Creole Sauce over fish. Bake, uncovered, at 350° for 40 minutes or until fish flakes easily when tested with a fork. Transfer to a serving platter. Garnish with green pepper and lemon.