Reading Philosophical Investigations I came across this discussion of The sword Excalibur: "The word Excalibur is a proper name in the ordinary sense. . ." But in the German text, which is en-face, has no mention of Excalibur. Rather the sword is Nothung,, the sword Siegfried places between himself and Bruenhilde to guarantee her chastity. It is obvious translator has substituted the English sword for English readers. It saves a footnote, and the point of the passage is that a name applies whether a thing exists or not, so that the idea that there is a direct relationship between a noun and a thing doesn't really make sense. Both are famous swords within their own cultural context.
Yet, i will say, i would have preferred the original sword, even if i am less familiar with the legend and the Wagnerian Opera. I like to get the feel of the cultural context of the original. I like a bit of otherness, strangeness.
I see this done a lot with Greek texts too. A strange or difficult idiom or reference is substituted for with a familiar one. In The first elegy of Kallimachos, I remember, the translator wrote "from an ancient people." In the Greek the word was not ancient but προυσέληνς, "before the moon", because the people were said to be so ancient they were older thαn the moon. A much more poetic and interesting take.