I found a modded SMP that is all about geopolitics on an Earth style map. It uses a Create based modpack with lots of addons and extra mods like Superb Warfare Agricraft and Simple Planes.
The main idea is to found your own country and try to grow it. There is a land claim system so you can claim a country for yourself as long as it is not already taken. You can also bring friends and run it together.
It feels like a mix of industry building and military power. You can build up big factories and machines then push for world domination if that is your thing. If you want politics conflict and people making deals then breaking them this server seems made for that.
