It's not really what you asked for, but subtitles that you download from websites like zimuku.com or zimuku.cn have dual language versions: separate English and Chinese flag means the ZIP file contains separate language subs, pirate flag means it has one set of subtitles containing both languages - super useful if your video player doesn't support displaying more than one set or you don't want subs at the top of the screen).
I really hope it supports Hanyu Pinyin. So excited.