Many people attribute the many differences between Earthbound Zero and Earthbound to the fact someone named 'NEO DemiForce' translated Mother poorly into English. But if I remember correctly, Neo BOUGHT the sole translated cartridge from a man who won it in an auction. That means that Neo didn't poorly translate the cartridge, but that he just dumped the correctly translated cartridge.

And since if Earthbound Zero had been or would be released as it was on the cartridge Neo bought, Earthbound Zero and Earthbound, or Earthbound and Earthbound 2 as they would be known, would be the accepted canon in North America; and if Giegue and Giygas have the same name in Japan, that would be the accepted canon in Japan.

It wouldn't be the first time a series was translated differently into English. For information on that, post a topic on the forum titled 'Q: Is it up to us?' Canon is known as released games accepted in a certain area.

To back up the title, it is up to us, to make our own decisions on what we believe, and what we don't; but not to try change the names so it is like the Japanese.