Combine shallot and garlic in a food processor and process until a paste forms. Place in a large bowl. Add soy sauce, rice wine, and sugar; stir to combine. Add pork, cover, and marinate in the refrigerator, 6 hours to overnight.
Set oven rack about 6 inches from the heat source and preheat the oven's broiler.
Take pork out of the marinade and place in a clean bowl. Reserve the marinade. Add oil to the pork, stir, and thread pork onto skewers, 5 to 6 pieces per skewer. Broil, basting with the marinade, until browned and sticky on the outside, about 5 minutes per side. An instant-read thermometer inserted into the pork should read at least 145 degrees F (63 degrees C).