Preheat your grill to medium-high heat. If using wooden skewers, soak them in water for at least 30 minutes to prevent burning.
In a large bowl, combine the chicken cubes, barbecue sauce, olive oil, garlic powder, onion powder, salt, and pepper. Mix well to ensure the chicken is evenly coated.
Thread the chicken, pineapple, bell peppers, and onion onto the skewers, alternating between the ingredients.
Place the kabobs on the grill and cook for about 10-12 minutes, turning occasionally, until the chicken is cooked through and reaches an internal temperature of 165°F.
Remove from the grill and let rest for a few minutes before serving.