If the lightsabers from STAR WARS were to appear in either Jin Yong or Gu Long's wuxia universes, I think the swordsmen of those worlds would have a difficult time adjusting to the lightsaber...at least at first.
Wuxia swordsmen are accustomed to using material swords (usually made of metal) of certain mass and weight. The swordsman's familiarity with the sword's mass and weight and how these factors will influence its movement is key to his ability to wield the sword effectively. As we saw in Sai Mun Chui Sheut and (fake) Yip Goo Sing's introduction of their swords prior to their duel, the physical properties and dimensions of the sword were details that could not be overlooked.
Aside from the emitter handle, the actual lightsaber blade has no mass or weight. It's essentially like trying to wield a flashlight as a sword. The Jedi and the Sith were able to maneuver the lightsabers well due to their knowledge of the Force, but wulin fighters do not have that particular ability at their disposal.
The only thing comparable to the lightsaber is the 6 Mak Divine Swords, which is also a "massless" blade. A 6 Mak Divine Swords expert *might* be able to adjust to the lightsaber better than his material sword-wielding peers, but it still wouldn't be quite the same.