Voice Chat–Arma 3 - Task Force Radio - Setup & Beginners Guide - YouTube
Definitly, with C++ you can do anything, it’s just matter how much work is needed, now much UE4 has to . But it definitly will require C++ work or else you find a plugin that let you do something like that.
The solution you showing is using TeamSpeak with a plugin that seems to direct voice to right player depending on range and game only send position data to that plugin i assume. So to replicate it you would need to read how TeamSpeak plugins work and figure how to communicate from game to TeamSpeak plugin which can be done in countless ways of your choosing.
Could you create it on blueprints without ts3?
Yes, you can do anything in C++, and you can create Blueprint nodes for anything in C++ too.
To get it to work without TS3, you’ll need to learn how voice chat works and create your own, or implement an integration to another voice chat system. I don’t know how to do that personally, but the short answer is that yes, you can do it once you know how.