There is little to no documentation of foreigners trying to incite the American revolution in particular. The French as you know did not join the war until 1778, and are to this day known as one of the biggest factors contributing to the American victory. The Spanish initially were at war with Britain around 1779, disrupting the flow of British troops to the colonies somewhat effectively and causing conflict in Louisiana, but had little to no concern for directly helping the American colonies. Spain only had a concern of regaining the territory it lost to the colonies. Other than France being the major ally of the colonies, Holland and Spain are attributed with providing help financially. The former providing arms and selling ships while the latter providing loans. The American revolution essentially was mixed with a Holland/France/Spain v. British conflict as well.