Followbutton for guests in a other stream
If you are streaming together with a other streamer on twitch, you should be able to have a followbutton for him under your channel as well. (Until the stream ends)
We've already seen something like at the SGDQ-Stream, where the current speedrunners had a follow-button under the stream.
(Sorry for grammar errors. I hope you can understand what I mean)
This has been fulfilled with being able to tag channels in stream titles. The other streamer's info is easily shared, and they can be followed without ever leaving your page.