Can't find a mod like that, but from my experience playing tactician, the enemy is simply more plainly effective - sometimes their decisions clearly could be better, sometimes they are the best possible decisions, but they aren't doing everything perfectly. Also tactician is sort of easy, even on honor mode all you have to worry about is the voidwoken fight where you get the ring and the genie fight. Act 2 once you get gear and especially act 3 don't contain much of a challenge.
