Wash the short ribs, removing any stray bits of bone, and allow to drain for 30 minutes.
Whisk together the soya sauce, sugar, honey, garlic, pepper, water, sesame oil, and plum wine until the sugar has dissolved; pour the mixture into a large reclosable food and freezer bag. Place the ribs into the marinade, squeeze all the air out of the bag, seal, and chill in the fridge for at least 24 hours (place inside a dish to avoid any small leaks).
The next day, remove the ribs from the fridge and allow to come to room temperature before cooking. Remove the ribs from the marinade and discard the marinade.
Preheat the BBQ to a medium-high heat and lightly oil the grill grate. Cook the ribs on the BBQ until browned and no longer pink in the centre, 4 to 6 minutes per side.