A Plague Tale: Requiem - HDR Optimized Settings (Patreon)
Content
The game DOES USE/APPLY Xbox & Playstation HDR Calibration app settings.
The game has a good HDR implementation as it actually reads and applies the system HDR settings directly to the game (up to actual 2.000 nits Peak HDR Luminance).
The game also offers an HDR slider which will act as a general Paper White (or Gamma) adjustment of the image:
That said, the example picture brightness does not accurately represent the actual luminance you will have in-game, but -1 Click from middle value will provide a balanced exposure/gamma.
If you find the image too dim, you can increase it by +1/+2 clicks.
If you find the image too bright/clipped, you can decrease it by another -1 click.
BONUS:
Disable Chromatic Aberration in order to improve both visual clarity and performance stability.