With respect to diplomacy, you get a +1 influence if you have a treaty established with a faction. However, if the faction that you have a treaty with is at war with another faction (lets say Altar), there is no penalty between you and Altar.
Altar should be miffed that I have a treaty on the go with a faction they are at war with. There should be at least a -1 influence hit. But currently, Altar is indifferent to it.
I'm still a bit new at the game, so maybe these penalties emerge as I unlock more meaningful types of alliances? Or does diplomacy operate within bubbles that only have two-way exchanges - and no domino effects?