VS2019 preview 1 is available and comes with a number of new C++ features, including Live Share for collaborative coding.

Announcing Live Share for C++: Real-Time Sharing and Collaboration

By Nick Uhlenhuth

From the article:

C++ developers using Visual Studio 2019 16.0 Preview 1 or Visual Studio Code can now use Live Share. With Live Share you can share the full context of your code, enabling collaborative editing and debugging.