Hmm, I installed the planetary diversity base mod, and ran it with just my two mods you mentioned, and from what I can see in that nothing should conflict with my mods, I have 2 questions for you:
1: does it always spawn in exactly 7 of your custom empires, or does that number fluctuate?
2: when setting the name for your custom empires did you just hit the random button and leave it at that?

2 causes problems because of something in the stellaris back end, it is easy to get around by just renaming your empire, even to the original name

Help please, I am using this and 'all custom empires'.
I use UI overhaul, At war ship sections, a bunch of basic portrait mods and a bunch of basic ship sets.Cybrxkhans name lists, and Plaetary diversity.

I have no created empires which I do not have locked in for my game. I created 14 and have my game set to 14 AI. All are locked in. I start the game and ~7 are rando empires and about 7 are my created empires. I am not using Sol or Deneb, Common ground or anything like that.
What am I doing wrong? Load order? Thank you for any help any one can give.

hmm, that's bizarre, the empires shouldn't even exist in the code to spawn, United Nations of Earth will spawn if there's a human Lost Colony, but the rest should never spawn, as they don't exist.. I would like to help but I have no idea what would cause this to happen, and can't replicate it

They no longer appear in Empire select, but they still spawn nevertheless when i genrate a galaxy.

When you go to start a new game do the paradox empires still appear at the bottom of the list of empires that you can choose?

Unfortunately it seems the mod doesn't work, i've logged into a game and i came across the Empire of Humanity/Commonwealth of Man (or whatever it was called), more so, it seems to actually cause more Paradox Empires to spawn even if I cap the AI empire spawn limit to the same amount of custom force-spawned Empires I have.

Thanks Dawix, it has been fixed

The update doesn't work.It will shows empires from the necroids, toxoids, lithoids, plantoids, and aquatics species packs.

Yes, this only affects the prescripted empires, the ones that appear when you go to select/create an empire at the bottom of the list, It sounds like you might want the mod linked in the description, which removes the random empires that appear (or possibly both of these), which will only affect the standard empires

Fallen empires, marauders, traders, mid and end game crisis still spawn though right?

Uploaded a fix that should work, has an unused empire that stops the crash

I did some testing, it seems that if you have a mod that adds empires it doesn't crash, will try and get a fix out today

huh, it did crash when I ran just this mod, but when I used all of my usual mods it doesn't crash...

This mod causes crash at start up.

game crush