I have a weird oddity.
I have a planet where I built
Harmony Crystals
Galactic Bizaar
Diplomatic Translators
The Anti-Matter/Fusion/Quantum Power Plants no longer show up in the available projects.
I decomisioned all buildings other than those 3 mentioned (I can't remove them of course), and I still can't build the power plants.
The planet is a class 22 toxic world. I have all Toxic World colonizer techs researched.