Add the chicken legs directly into the crockpot. Sprinkle garlic powder, onion powder, oregano, paprika, salt, pepper, and cayenne evenly over the chicken. Pour barbecue sauce over the top and gently toss it all together to coat the legs evenly.
Cover and cook on low for 3– 4 hours or until the chicken is tender and cooked all the way through. Serve and enjoy!