Whisk vinegar, soy sauce, sriracha hot sauce, and olive oil together in a large bowl; add brown sugar and stir until dissolved. Mix green onions, garlic, black pepper, sesame seeds, ginger, and five-spice powder into vinegar mixture until marinade is evenly combined.

Place short ribs in a large reseable bag and pour marinade over ribs; coat with the marinade, squeeze out excess air, and seal the bag. Marinate in the refrigerator for at least 3 hours.

Preheat grill for medium heat and lightly oil the grate.

Remove ribs from marinade and place on the grill; cook for 6 to 7 minutes. Flip ribs and spoon marinade over second side; cook until meat is no longer pink, 6 to 7 minutes more. Turn grill heat to high and cook ribs for 1 minute more per side. Remove ribs from heat and place on a plate; let rest for 5 minutes.