Thanks for raising this. I have done this myself and can show you how to do it.
1.) Create the Team with the required users, this creates an Office 365 Group 2.) In Stream, create a Channel and link it to the Office 365 Group 3.) Select the Channel and go to Membership, add the members of the Team 4.) Upload the Videos you need to the Channel 5.) In the Teams Channel, create Stream Tab with Channel set as the Channel you created in the Stream Portal.
That should work, then all members of the Team should be able to see the videos. They do not have to go into the Stream Portal to view them. If you are adding the New Members to the Team you will also need to add them to Membership within the Stream Channel. It does not do this automatically at present.
This all works on a full Office 365 licence. I do not think it works on a free licence with the Teams Trial because this licence would not contain a Stream Plan which is needed to consume the video.
Hope that helps and that I have answered your question.