I have a Mi9T and the super wallpapers APK by Linuxct is working fine. I'd argue that it would still make sense to enable super wallpapers on such devices (it's not like those wallpapers are set by default).
I have the same screen, the setting for "Global dark mode" is no longer in this screen. You can only change the wallpaper, schedule, contrast and toggle individual apps on/off.
Great version, lots of fixes. There's just one very annoying thing compared to MIUI 11 and that's the "global dark mode" option that's missing in the menu. If you search for it in settings you find it, but it's not visible/toggle-able.