Someone can do something related to Wechat? 

I would like my members can access easily from wechat to my site, and from my site send message to wechat. 

Or whatever someone can give me any good connect to wechat solution. 

Some ideas:

(Force or pop-up suggest) to follow your WeChat official account (or add your WeChat as a contact) to access forums (or a specific forum). 

The problem is nobody(ips staff and 3party) interested in offer this skin feature. 

That's because most Chinese people only know Discuz; they haven't heard about IPS or even Xenforo. In their world, forum software means either Discuz or phpwind.

Given this situation, there's no demand and developers wouldn't have the incentive to supply.