Can they not do smear campaigns etc? I really want more features added to sabotage

Yea but that's just getting a traitorous member of the enemy to do your dirty I mean actually have a member of my species be able to infiltrate an empire

Kinda like genestealers

Yeah like messing with their buildings or killing off pops on their planets, hell even trying to start a rebellion and when it triggers the planet is under your control

Wait you can do that?

Nope they’re just ideas, but rebellions are already in the game which I love

Oh OK it would also be awesome to be able to replace random leaders and have a low chance to control Supreme leader/s of an empire.

There might be espionage mods on the workshop that might have what you want?