Change users names automatically

[Realworld404]

I recently attended a virtual conference where some attendees were labeled as VIPs as soon as they logged into the meeting. I'd like to do the same with my regular meetings. How might one accomplish this? The participant list would look like

John Doe
Donald Duck
*VIP* Mickey Mouse
Minnie Mouse
Huey McDuck
*VIP* Scrooge McDuck
Louie McDuck
...

[Realworld404]

I suspect the solution lies in renaming participants or changing their display name via API but I can't find an API for that. I see how I can manually change individual display names once they log in, but that is cumbersome and doesn't scale. 

I have a list of premium, paying members to my weekly meetup. When they join, I'd like their display name to be badged with some sort of recognition so that the free attendees can see the quality of paying members.