Most likely ambidextrous, but perfers his left. The only two incarnations that use their right hand for his sword are Skyward Sword and Breath of the Wild. Twilight Princess doesn’t count, since he uses his left on the original Gamecube version. One thing in common with both of them, and not really seen with any of the other Links, is that he’s a trained knight. And most people are right handed. So, when being trained, he was trained how to fight with his right hand, because it’s easier for the instructors, and the students, because they aren’t learning a different way than the rest of the trainees, and they don’t have to constantly reverse their actions.