How do i get FSR 4.0 on RX 6800?

[Rebether]

Tried to do a method with driver modification from Reddit, but it causes problems with some games and makes them unplayable.

I don't need a FG, just an upscaling itself.

Got optiscaler on Dying Light The Beast, but my only option is FSR 3, which is available natively, so really no point in OptiScaler.