Sever Voice Channels.

You should be able to ping people, within a server voice chat in a similar fashion to that of a discord group dm.

This would mean, whoever is getting pinged, would receive an on screen notification and audio notification, similar to when someone starts a call on a group dm.

This could be implemented in a way, where a role is tied to a voice chat, and when the sever detects that anyone has joined that particular voice chat, everyone who has the associated role gets pinged.