Are you saying that the same translation of “Light” is used in both places? If so, then I think best to use the translation that is right for the Theme. The "Leveller is no longer enabled by default in Audacity and should be removed. To be honest, I’d forgotten that it was still there.
Thanks for asking about it. I’ve posted to the developer’s mailing list to suggest that Leveller should be removed from the code (at a suitable time, which is probably not now as we are so close to releasing 2.2.0).