Hi
You can't put big flares in VR mode because it will completely destroy the immersion. The VR mode is used to mimic a real "eye" view. The lens flare effect occurs only as a result of light refraction in the lens. The human eye does not have this effect and it is not advisable to magnify it in VR.
Of course everything can be programmed and changed, but answer the question: Do you want maximum immersion or rather special effects in VR mode?
Piotr