Wifi Calling Using the Network

Help
#1

Hi, I saw in one of the videos that wifi calling was coming. Is this feature out yet? If yes, could you provide a link where I could get further information?
Thanks

#2

Hi Wisk! Welcome!
What do you mean by wifi calling? Which video?

#3

See about 37.35min in this video LibreRouter - YouTube
It seems it was posted in 2017.