1.1 Onwards
As of RimWorld version 1.1, AutoOwl has now been made part of a new mod, Tiny Tweaks: https://steamcommunity.com/sharedfiles/filedetails/?id=2017485672
1.0
Note: This is an updated version of AutoOwl by Dazz Aephiex, additionally no longer needing HugsLib (now solely uses the Harmony Patch Library by Brrainz, included with this).
GitHub source code: https://github.com/XeoNovaDan/AutoOwl
Anyway...
This mod makes it so that colonists and prisoners with the trait Night Owl will have an alternative initial schedule to avoid working during the day and suffering -10 mood as a result.
Regular Colonists: sleep at 0-5 and 22-23
Night Owls: sleep at 11-18
This mod only changes the initial schedule upon pawn generation; existing Night Owls will NOT have their schedule changed.
Incompatibility: Issues have been reported with Humanoid Alien Races 2.0 in the past -- not confirmed with the latest version though
Old Save Compatible: Yes
Safely Removable: Yes
Credits:
Dazz Aephiex - Original mod
Dingo - Contributions regarding bugfixing and compatibility
Brrainz - Their fantastic Harmony Patch Library