weChat is something we've investigated in the past for implementation and plan to do. They use a different method of authentication than most other social networks with their QR code scheme, but it didn't look like it would pose any problems for integration.
When we were evaluating the next features for JFBConnect, the Facebook breach happened, which diverted all of our resources to updates to maintain compatibility. We just released v8, which has those updates. Our next focus is on GDPR compliance and compatibility with the upcoming Joomla 3.9 release. After that, I can see weChat being something we'd work on next, but we haven't redone our internal roadmap since earlier this year, so I can't say that for sure.
I hope that helps answer your question, but should you need anything else, please let us know.
Thanks,
Alex
weChat support
