Currently only four Active Participants can be visible in the Microsoft Teams Meeting. Microsoft is working and the feature is due to release with the capacity increased from 4 to 9.
Feature has started rolling out Globally should be completed by end of May 2020.
Video have the limit of 4, but is increased to 9 at the same time. About sharing screen: only 1 can share his/her screen. When someone else start sharing his/her screen, it will stop the previous one.
