Project "GG - Voice of Heroes"

2) And now I am ASKING THE COMMUNITY directly about this possibility - HOW TO DO IT? WHAT TOOLS?

You can trim it directly on Twitch, or you can record it to your hard drive and edit it in a video editor.
I can implement all of this, in principle, but it will require some effort, I apologize.
Besides, the picture quality from Mikog and TV is far from ideal, and I won't be able to create a truly "perfect" result.

If you are really interested, I can comment on something and then try to edit it, just for a test, but I'm not sure the result will be worth the effort.