I bet the oar NP would be a bit like Bazett's Fragarach. When the enemy uses their ultimate attack, she can invoke it to reverse time and interrupt them by shining sunlight in their eyes. It'd be a technique she invented to defeat Kojiro in their famous duel, since she realized that the only way to counter Tsubame Gaeshi was to stop him from using it in the first place. That'd be what I'd do anyways.