Perhaps for nations without explicit support, you could create procedural naming schemes? Capital city, capital province, culture adjective, collective nation noun, nation-adjective [empire, kingdom, etc.]?

That sounds a bit complex and I’m not sure the modding language would even allow me to do something like that.

I'm fairly certain it's possible with some dynamic localization. The documentation for it is pretty confusing, though.

One extra name for thee "Sparta Rename List"; *Laconia*. It was an optional formable country in Imperator: Rome's early days I believe.

Give me the option to change 'Roman Empire' back to 'Rome', please and thank you.