Car and flight sims where it's easier to bolt on and makes sense: PCars, Assetto Corsa, iRacing, LFS, DCS, War Thunder. It's taken them all a few years from the point of initial support to get the menus and UI working correctly, tho. But they are all doing it and realize how VR from here on in is almost required in sims. We'll have more resolution soon enough, but when you've got a HOTAS or a wheel setup... man, it's tough going back from that presence, immersion, and headtracking.
Also simple tabletop stuff like Blazerush and Legend of Dungeon.
Something with an FPS component? Not so much. You have things like Alien: Isolation or Dying Light that planned on VR, then realized they couldn't make it a GOOD experience so just dropped it and left it as an undocumented mode and gave up on VR officially added later. Valve attempted experiments with HL2 and TF2 but even they couldn't make it work to their satisfaction and quietly dropped it too. And that's VALVE. They had a huge interest in making it work. Carmack threw a big chunk of his brain at Minecraft for a year and a half, and all the press on it still mentions people being sick. The Gear VR version he suggests you use with a swivel chair is out but the Rift version is still being tweaked, no doubt due to all those articles mentioning ginger treats and sim sickness.
Nothing done on CryEngine 3 that I can think of.
It's relatively easy to just switch things to 3D rendering and make the camera work for VR. Much harder is all the UI, animation changes, reworking the menus, removing all the graphical tricks engines use to cut corners that don't work in 3D, problems of world scale that work in 2d but look utterly wrong in VR, and solving sim sickness issues with locomotion.
CIG has done ZERO of that. They don't have anybody working on it and haven't planned for VR support considering the implementation of the UI and those awful animations.
That doesn't sound like they can deliver VR support to SC and S42 as planned. If Valve can't solve FPS locomotion, the crobber baron sure isn't going to. He should just TELL US. Not once have we had honest talk on the subject. Just promises, dancing around the rude reality of it. They aren't being honest with us... what else is new.
The only VR support these tech demos will ever have is via VorpX for the iron-stomached.