BetterDisplay

BetterDisplay lets you convert your displays to fully scalable screens and manage display configuration overrides.

Also, it allows brightness and color control and provides XDR/HDR brightness upscaling and full dimming to black. Furthermore, the tool helps you create and manage virtual displays (dummies) for your Mac, create Picture in Picture windows of your displays and gives you a host of other features to manage your display's settings easily from the menu bar.