I don't know there is a nickname for red haired people in China. There are a few Chinese who are red haired by birth, but not many really. Maybe people would just call them '红毛', which literally means red haired.
A century ago, Hollanders invaded China and then they were called '红毛鬼' or '红毛子', in an evil sense. After that, westerners and Russians, especially those who ever did bad things to China, were often called as that.