If I show an alert without any buttons, a default button is "OK". In Korean iOS it is "확인" and in Japanese it is "OK" as well.
So if I can refer localizations from iOS, it's much easier to translate my app. If not, I have to translate every my custom "OK" buttons and so on.
It seems there is no such way to do like this, but if there is I wanna ask you how to refer any strings or any localizations from iOS.