Hello, a question directed mostly to Epic Games stuff. Are you planning to add any kind of support for Microsoft Mixed Reality headset? Unity is already doing this and they got some promotion directly from Microsoft
Native support probably not, as Tim Sweeney (CEO of Epic) is against Universal Windows Platform (for good reasons), so Unreal is not supporting UWP, which is a requirement for Windows MR. Microsoft created their own Unreal branch for WMR, which you can download from here > https://github.com/MICROSOFT-XBOX-ATG/MICROSOFT_UWP_UNREAL/tree/dev_MixedReality. But it’s not very stable and expect major issues.
Microsoft also created a bridge between SteamVR and WMR, so if you download this on Steam, you can use WMR headsets in Unreal as if they were Vive and it’s been reported to be working really good.
At last, Microsoft joined Kronos group to work on OpenXR, which is a unifying platform for all VR/AR devices that WILL be supported by Unreal and mostlikely by WMR devices as well (why else would they join?), so you can expect native support thru OpenXR once that is released. I would expect that happening sometime during 2018.
Just a heads up, it was working well in 4.17 but broke in 4.18, see Help with VR regression in 4.18 - VR and AR Development - Unreal Engine Forums.
I’m hoping it gets fixed again for 4.19. 
Thanks, can you share some info about why Tim Sweeney is against UWP? I’m just curious about it.
I also tested Mixed Reality Headset with UE4 in 4.17 version using Steam VR and VR template from Epic. I can tell that the project is running… but it crashes after few minutes (1-2min) - randomly. So it hard to call it working really good.