I feel like there's a feature here that makes it accessible to apply certain traits together that would normally be restricted if you were to play in vanilla mode.

For example, say I wanted my sim to have the Shy trait, but they're also a Social Butterfly too. Isn't that a thing here? I've had these installed before (nraas mods as well as a certain mod at MTS regarding unlocked traits and ages), but couldn't figure out the issue for it not working anymore.

Much of anything is INDEED appreciated!

~ Thanks in advance!

Do you recall the action for that, so I can test and see?

I haven't been able to apply conflicting traits via Master Controller. The conflicting trait will not even make it to the display stage and your sim will be missing a trait.