I found that when starting a new game, clicking on the “Mindwardens” origin in the origin selection screen causes the game to crash. When I disable this mod, the crash no longer happens. So I believe this mod might conflict with the newly added Mindwardens origin.
I’m not sure whether AI empires choosing the Mindwardens origin would also cause a crash, but it’s certain that players cannot select this origin. Other origins (including those added by the Gigastructural Engineering & More mod) work fine and do not cause any issues.