In a large mixing bowl, combine the ground beef, breadcrumbs, egg, garlic powder, Worcestershire sauce, pepper, and salt.
Form the mixture into 1-inch meatballs and place them in the slow cooker.
In a separate bowl, whisk together the BBQ sauce, drained crushed pineapple, and soy sauce until well combined.
Pour the pineapple-BBQ sauce over the meatballs in the slow cooker, ensuring they are well-coated.
Cover and cook on low for 6-8 hours or high for 3-4 hours.
Once cooked, stir the meatballs gently in the sauce before serving.
Serve hot with rice, pasta, or as a standalone appetizer.