Combine soy sauce, water, sugar, onion flakes, Worcestershire sauce, vinegar, oil, garlic powder, and ginger in a medium bowl. Stir until sugar dissolves.
In a large resealable plastic bag, mix the wine, soy sauce, olive oil, brown sugar, ginger, garlic, and pepper. Place steak in the bag, seal, and refrigerate 8 hours, or overnight.
Preheat an outdoor grill for medium-high heat.
Remove steaks from the bag, and discard marinade. Place steaks on the grill and cook 6 to 8 minutes per side, to your desired degree of doneness. The internal temperature should be at least 145 degrees F (63 degrees C) for rare. Allow the steaks to sit about 5 minutes before slicing against the grain, and serving.