In a medium bowl, whisk together barbecue sauce, teriyaki sauce, minced garlic, and freshly grated ginger until well combined.

In a large bowl or resealable bag, combine the boneless, skinless chicken breasts with the marinade you prepared. Make sure each piece is thoroughly coated, then seal the bag or cover the bowl. Refrigerate for at least 2 hours, or up to 8 hours.

Once the chicken has marinated, it's time to assemble your skewers. Thread the marinated chicken, fresh pineapple chunks, red bell pepper pieces, and sweet onion wedges onto skewers, alternating each ingredient.

While assembling the skewers, preheat your grill to medium-high heat, about 375°F to 400°F.

Place the assembled skewers on the hot grill and brush them lightly with oil. Grill for 10-12 minutes, flipping occasionally to achieve even cooking.

During the last few minutes of grilling, brush the skewers with any reserved marinade for extra flavor. Once fully cooked, remove the skewers from the grill and let them rest for a couple of minutes.