What are the effects of sharing intrigue with rivals?

One immediately obvious effect of sharing intrigue with an AI player is the diplomatic bonus you receive, but I'm curious if there are others. Can anyone verify the existence of any of the following when sharing military intelligence such as a planned sneak attack or impending invasion?

1. Does the attacker receive a diplomatic penalty from the target? If not, does this cause any change to their attitudes towards each other?

2. Does the target take steps to defend against it, e.g., building up defenses or moving its existing forces? This would make the most sense.

3. Does the attacker alter its plans strictly due to the sharing? In other words, does the attacker know that I've shared intrigued with their target and adjusts its plans immediately.

   Clearly the attacker may react to any visible actions taken by the target such as moving units, but this point is strictly about the attacker responding to the mere hidden fact that I shared the intrigue.

Solution 1:

Nothing happens unless prompted to initiate an action from my experience. I have noticed AI benefits to diplomacy as Affine mentions in comments to your questions, but have not yet encountered any negative effects or reactions. You seem aware of the overt actions being recognized, such as troop movement, so just play it safe and you should be good.

So to formally answer; There is a positive impact to diplomacy with nations you plot with, but no negative impact to those you plot against. The AI also does not share the intrigue with the enemy opposition.