We today just allow the person to be in lobby and decide whether to admit him or not. But post this pandemic, the physical meeting and virtual meeting have not difference. We would need a way that the person in lobby area can communicated from the Host and alternate host in meeting. So once can communicate to the attendees and another be the host of meeting.
Once the person is meeting, he should first be in the lobby and from them host or alternate host can greet him and have a virtual connect. Once they are comfortable and host deems fit to allow the person in the meeting, he should be allowed to do so. Also, during the meeting if the host wants to communicate the another person he can move them to lobby to discuss.
This is to replicate the in person meeting experience of the real world in virtual