In a large measuring cup or medium bowl, combine the BBQ sauce mix pouch, pineapple juice, and chili garlic sauce; whisk until smooth. The sauce will thicken as it stands.
Reserve about 1/3 cup of the sauce and refrigerate it for finishing. Put the wings in a large resealable zip-top bag and add 3/4 cup of the sauce; seal and toss to coat evenly.
Marinate the wings in the refrigerator for at least 30 minutes, or up to overnight for more flavor.
When ready to bake, preheat the oven to 425°F (220°C). Line a baking sheet with aluminum foil.
Remove the wings from the bag, discard the bag and any leftover marinade from the bag, and arrange the wings in a single layer on the prepared baking sheet.
Bake the wings for 35 to 40 minutes, flipping once halfway through, until the internal temperature reaches 165°F (74°C) and the wings are browned to your liking; watch closely near the end to avoid burning the glaze.
Transfer the cooked wings to a large bowl, pour the reserved ~1/3 cup sauce over them, and toss to coat evenly.
Garnish with sliced green onions and serve immediately.