Sadly not available for Wayland because of Wayland's architecture. KDE and GNOME have some functionality built in but I don't know how good it actually is compared to redshift.

That's not quite true: the compositor needs to support it. There's a protocol [1] for it that's supported by a redshift with a patch [2]. It also works out the box for any wlroots-based [3] compositors, like sway [4].

[1] https://github.com/swaywm/wlr-protocols/blob/master/unstable...

[2] https://github.com/minus7/redshift/tree/wayland

[3] https://github.com/swaywm/wlroots

[4] https://github.com/swaywm/sway