Warner

I just tried setting up website limits via Screen Times's "App Limits" feature.
System Preferences > Screen Time > App-Limits > [+] > Websites

I found the limits only applied to Safari and not Orion. Firefox doesn't seem to support this feature as well. It would be nice if it would be possible in Orion.

Edit: Another user on the Discord server mentioned that there is an API for doing this:
https://developer.apple.com/documentation/screentime/stwebpagecontroller