The creation tool also just lets you save the iso - but for some reason the media creation tool gives you a different iso than if you spoofed a non-windows user agent on the windows download website so that it gives you a direct link to the iso instead of getting you to install the creation tool. And for some reason only one of them worked with DISM to repair my system in order to be able to run windows update successfully.
Federation sounded interesting so I looked at the website and it sounds like on prem can’t yet federate with people using “cloud” which I guess is the hosted version - they can only federate with other on-prem instances.
It looks promising though and would be cool to host my own instance and still chat with friends.