I don't think he'd have to change it, though I'd say that it doesn't fit his character very well. I think he may want to make the weapon something different to make it easier on the QMs, but he shouldn't have to change it unless he starts claiming he can use electric attacks.
Here are some effects QMs may want to use:
Unlucky - If not lucky, you get the worse out of 2 rolls, if Lucky, you get normal roll
Aflame - Causes N+1 damage each turn (1, 2, 3, etc.) until put out by a water bomb or a water elemental attack.
Worsening poison - Causes N+1 damage each round (1, 2, 3, etc.) until remedied.