Actually it is possible now to capture 360 video from game directly and in real time.
D3DGear is developing a new technology that is capable to capture VR 360 video from game directly in real time while users are playing a game.
You can take a look this youtube channel, it has some sample VR 360 videos that captured from game directly, enjoy!
https://www.youtube.com/channel/UCV-6pHsF2kqLrxlvLPyn60AYou can contact D3DGear (support@d3dgear.com) if you need more information.