Hey, Chinese Mandarin speaker here. Yes, HK uses traditional not simplified. Mainland's orienteering federation is the Orienteering Association of China (OACN) and I think they're holding a junior championship soon. Here is their website: http://oacn.sport.org.cn
There's some good info there all in simplified mandarin. I usually use 定向运动 (dingxiang yundong) for orienteering searches and seems to work well. Of course probably more stuff on Baidu, etc than google for Chinese content. 祝你好运!