Preheat your grill to medium-high heat.
In a large bowl, combine the chicken thighs, barbecue sauce, pineapple chunks, sliced bell peppers, sliced onion, olive oil, garlic powder, onion powder, salt, and pepper. Mix until the chicken and vegetables are well coated.
Lay out the aluminum foil sheets on a flat surface. Divide the chicken mixture evenly among the sheets, placing it in the center of each.
Fold the sides of the foil over the chicken and vegetables, creating a sealed packet. Make sure the packets are tightly sealed to prevent any leakage.
Place the foil packets on the preheated grill. Cook for about 25-30 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F.
Carefully remove the packets from the grill and let them rest for a few minutes before opening. Be cautious of steam when unwrapping.
Serve the Hawaiian BBQ chicken directly from the foil packets, or transfer to plates.