After i found code for light propagation volumes(for the ones that dont know, its the same global illumination system that Cryengine uses), i investigated it, and after some time hunting it through the code found the way to enable it.
Yes, you can use **Dynamic Global Illumination ** right NOW.
The code is still a WIP, a beta feature, it WILL change in new releases, and its not completed at this moment, it suffers for really severe light leaking bugs, and i wouldnt ever recomend it for real development, this is only for trailblazers and people who love to tinker with stuff.
How to enable it:
I found a CVar config in the light propagation volumes, to enable them, you need to open Engine/Config/ConsoleVariables.ini, and add this line under [Startup]
That config variable will enable their use. Now, to use them, you need to disable lightmass ( Force No Precomputed Lighting set to TRUE in global settings)
Then you need to add a directional light and set its variable Affect Dynamic Indirect Lighting to true.
There you go, now you have dynamic GI. For fine tuning, add a Post Process Volume to your level, and tweak the settings in the Light Propagation Volumes part.
For the ones that want to know how it looks, RedBox, also a betatester, created this awesome level and added dynamic GI to it.