I feel my team was way more productive when we all were whiteboarding together when designing new solutions.
Recently I have been day dreaming about VR whiteboards and tablet assisted whiteboards as I feel the tactile sense of a pen would help.
What are you using today?
1) Get the cheapest iPad that supports the Apple Pencil. The 2018 non-Pro was this for me last I looked.
2) Get the Google Jamboard app (not the Jamboard hardware, it is not at all worth it).
3) Share the "jam" with yourself on a different device (a nearby laptop)
4) Screenshare the laptop.
Things I think any virtual whiteboard scheme needs to have:
1) You need to be able to see people's faces! If you can't see the people in the video call, good luck having anything feel natural.
2) See #1 again. Having the laptop drive the video call is important so you can configure it to see everyone's face while you present.
3) being able to use a pen to write and a finger to erase (if you have to open a menu, fail. sadly the jamboard app also gets this wrong though their way overpriced hardware gets it right)
4) ideally you have the ability to have an infinitely scrolling whiteboard. Jamboard doesn't do this, but it's close.
The Jamboard app also works on phones so other people can fairly easily join in and contribute. This scheme has its problems, but holy crap, so many whiteboard apps focus way too much on fancy new widgets and shapes and text and whatever and not enough on getting out of the way.