The Japanese names of Stands that have kanji and katakana are never known by the literal kanji reading. Star Platinum is never referred to as "Hoshi no Shirogane" in Japanese. It is always "Sutaa Purachina". Adding information regarding the literal reading of the Japanese text to this website is incorrect and irrelevant to JoJo.
But I told you this exact same thing almost exactly 1 year ago. You should not add "Hoshi no Shirogane" to any page here. Ruby is not used for romaji. It shouldn't even be used for the furigana seeing as parentheses are easier to read.