Niwa (丹羽):

1. Niwa Nagamitsu (丹羽长光), Niwa Changguang: from 500 years ago (Haran Geppaku Futsu weapon description)
2. Niwa Yiqing (丹羽义庆): 100 years ago, adopted into Kaedehara clan, defeated by Scaramouche but spared when Scaramouche learned that Yiqing was from the Niwa clan. Scaramouche said that his name is Kunikuzushi (国崩).

Kaedehara (枫原):

1. Fengyuan Jingguang (枫原景光), Kaedehara Kagemitsu
2. Fengyuan Yiqing (枫原义庆): adopted, originally Niwa Yiqing
3. Fengyuan Jiutong (枫原久通), Kaedehara Hisamichi
4. Fengyuan Jingchun (枫原景春), Kaedehara Kageharu
5. Fengyuan Wanye (枫原万叶), Kaedehara Kazuha

Genshin sometimes like to play around with the family name and given name, as well as the Chinese characters and their romanizations (whether in the Japanese on/kunyomi or English language). So in the long run, the pronunciation of Chinese characters can change over time and can even vary across space and different regions. What lasts forever though is the Chinese character itself, the pictogram.