if you don't speak cantonese, I suggest you do not work in HK. You will find it very uncomfortable since you will get discrimiated. Yes, it's common to live in Shen Zhen. But you have to spend 2hrs for a trip.
2 Questions about working in HK: (1) is it okay if the person speaks only English and Mandarin (2) is it practical to live in ShenZhen but work in HK?