Underhanded tactics against much bigger empires?
My situation is the following:
Playing as Kingdom of Milan, on the lower end of the great power list. I usually play tall, so my lands are basically northern Italy and a few caribbean beaches. I am on equal military tech level with most other powers. My total army is about 75k-ish big.
The year is around 1620, and the Ottomans pretty much gobbled up the Carpathian basin. They are fighting wars with the Gurkhans on the east- a fact that I wanted to abuse to annoy them. However, if I accept an invitation to war against them, they easily push me back with two armies by the total size of around 60k.
The question: is there any way in the game to use espionage or something similar to dismantle/weaken the Ottomans? Supporting rebels in this game always seemed to me as a waste of money, as it never produces any significant result.