It was about time that a new origin was announced. Hopefully, it will not be as overpowered as it sounds, though we doubt it will be balanced at first.
The new Origin coming to Stellaris with the Overlord Expansion is called the Teachers of the Shourd. It's a mysterious one, though it fits perfectly with the theme the OVerlord Expansion is going for, with cosmic manipulation in mind.
With the Teachers of the Shroud origin, your civilization was identified as a civilization of interest long ago by the Shroudwalkers, and they carefully guided you as their visions instructed. The player's species begins with the Latent Psionics trait and is in contact with the Shroudwalker coven.
With this origin, your civilization is treated as if it already has the Mind over Matter Ascension Perk, meaning Transcendence is not far away. On the other hand, though, you cannot pursue Synthetic or Biological Ascension, as is usually the case.
It will certainly be interesting to see how this origin will work and interact with the various other additions to the game such as the new Galactic Community lines, the Specialist Holdings, or even the Scholarium.
IN any case, it will give the galaxy some more dark and brooding mystery feeling, which it needs to get away from all the xenophobia players usually exhibit. ON second thought, though, it may just empower such behavior, who knows?