I believe Google Meet uses a special integration with Chrome/Chromium for screen sharing.
I do not think Electron will have access to it, as it is based on a much much more cutdown version of Chromium. So I do not think it will work.
If you need screen sharing you will need to launch it in a full chrome/chromium browser (one built with
enable_hangout_services_extension).
I'm not sure of how much of Chromium is changed in Electron. It may be possible, though it would take a lot of work to maintain compatibility as an individual considering how much code there is and how often it changes.
I am not sure why Google Meet doesn't just use the standard WebRTC API. It may be simply because of historical reasons / code inheritance from Google Hangouts.