In the wiki, it states that only 1 inhabitant trait can be selected but I feel like some of them would go together for thematic playthroughs.
Magic origins could be combined with many others like peaceful lands or rampant flora to make a magical Forest world.
Immortal spirits would go well with rampant undeath or demonic realm.
The trait increasing the amount of wonders around could go with literally every other trait as well.
I hope we are able to use multiple of this category of traits via patches in the future or mods.