Well, "Etoile" in french means "Star." (Musical/show.) Which is why in The Legend of Heroes: Trails of Cold Steel there's a restaurant with the name "Etoile," (in Japanese too) whose main feature is that they're a piano bar / music bar.
But I agree that the name should stay Etoile. If not, it should be named Idol or something that isn't two words put together into one word. One word names are usually easier tor remember, especially if they're catchy like "Idol." Quna becoming one of these in a future episode would make sense in that regard, if they planned to do that.