Ive been playing Morrowind for a bit, and Ive noticed that when I go from Edge Peek to VR mode, my eyes have to adjust somewhat significantly. I also notice I start getting a headache after a while, and it seems to me like it is from eye strain from crossing my eyes just a little too much (or going slightly wall-eyed, not sure). Am I missing a setting for this? Im playing in adaptive3D mode, if that makes a difference.
Please try the Z-Normal mode instead. Z-Adaptive does something similar to an autofocus to simulate a function of the eye called accommodation. If that causes eye strain for you, the normal mode with fixed convergence might be the better choice.