Combine the coconut milk, hot sauce, soy sauce, orange juice, and lime juice in a medium bowl. Add the shrimp and toss. Cover and marinate in the refrigerator for at least an hour. Toss occasionally. Meanwhile, cut the pineapple into 1-inch chunks.
Preheat the grill to medium-high. Remove the shrimp from the marinade (reserve the rest of the marinade for grilling). Put the shrimp onto the skewers, alternating with the pineapple.
Brush the grill with oil, then place the kebabs on the grill. Grill for 3 minutes, brushing with the marinade. Then, turn and cook for an another 2-3 minutes. Brush with the marinade again, until the shrimp are just cooked through. Remove from grill and place on a serving plate. Garnish with cilantro and green onion if desired. Enjoy!