Question Display-Specific Effects (Shader/PostProcess/...)?

Hello everyone!

I am new to HDRP, using this with VR headsets. I have an unusual problem related to multi-display view and post-process effects. Is there any way to show PP on one display and hide on another?

"Simply add second camera" not counts as a solution because scene contains heavy graphics and doubled renderer leads to performance issues. If it is possible to share rendering stages between two cameras and then apply different PP, would be great.

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Now some details because i bet it`s not clear what`s happening
I have VR project with smooth locomotion system. There is screen mask used in order to prevent (or at least minimize) motion sickness problem. This mask appears on start moving and lasts until velocity is zero.
So here is the problem: I dont want to show this mask on TV or monitor or any other display which is not VR HMD because it looks very weird.

P. S. sorry if there is an easy answer, it was not quite easy even to formulate and use google Trying to understand Graphics Compositor and other HDRP-specific concepts but this became serious problem for me...