Frankly speaking, UE4 doesn’t provide a solid out-of-the-box solution for room-scale VR. It works ok-ish if your Pawn just has a pair of hands and you are fine with it being able to stick its head through walls (in view of avoiding any oculo-vestibular mismatch that may lead to cybersickness). This said, as soon as you need a fully animated body which moves in synch with the VR camera and more control over positions and collisions, you need to be ready to write your own code from scratch or consider using a plugin which is specifically designed with room-scale in mind (e.g.@mordentral).
Luckily enough Epic provides some examples you can look into to get started. Couch Knights (even though somehow outdated) is one of them. Or you can look into the source code of Mordentral’s plugin and learn how he is managing it.
The problem is, as long as you have the VR Camera and the VR body inside the same Actor BP, the VR Camera will always be a child of the root component (through the CameraOrigin Scene Component) so you cannot really have the root component follow the camera when you move IRL because the hierarchy works the other way around. A potential solution could be to completely decouple the VR body from the VR Pawn and keep them “manually” in synch.
An extra complication is given by late updates. The camera and the motion controllers will always get an “extra” update during the Render Thread and after the regular Tick, so unless you disable it and accept a bit more latency, your VR body will always lag a bit behind the camera movements.
You are not the first one to stumble upon this issue, read here for example:
Some time ago @Slayemin has also looked into the very same problem and has proposed a solution which however requires modifying the Engine. You can read about it here:
Bottom line: IMHO there is no perfect (out-of-the-box) solution yet, definitely something that may benefit from some serious community discussion and joint work.