Voyager- In the Flesh
I found myself wondering if Chakotay would have blanched at the smooch with Archer if the crew had never gotten an actual glimpse of the Undine, enmity aside. I don't think I would say he's exactly Kirkian in his willingness to get physical in that way to advance the mission, regardless of the circumstances.
Harry's qualms about interspecies mingling were interesting too. The episode predated The Disease, but was way after Favorite Son, to say nothing of Prime Factors. Maybe the minimal aesthetic differences in each case calmed his concerns or it's just the continuity vapor lock at play again.