Ingame Video capture, Mac and Win

Hallo everyone,

i am interested in capturing a video from the gameplay of my game ( e.g. 30 fps .mp4 game resolution or so) with UMG Widgets displayed and woking on Win 10 and Mac OS. I think of something like:

In an (already existing) settings menu the user can set a a save path, file format, display or hide UMG and so on.
Then inside the packaged game the user presses a key and the capturing starts,
second key press stops the capturing.

I found several posts about this topic non of them seems to work:

Sounds quite complex to implement and i don’t think this approach would work with Mac OS.
The Direct X SDK is now part of the Windows Software Development Kit (SDK) so it is quite hard to get all this working. Maybe ffmpeg would be a solution . . .

Grab the Live stream and save it to disk would be an idea but i found no documentation on that.

Using the “Movie” function seems to work only in editor and not in a packaged game.

So is there any BP or C++ solution to this ? The best would be a Matinee start capture function i think.
If there is no solution then i think this would make up a good feature request. Audio capturing from game and/or an external microphone would be nice too.