The ogres in Blighted Village looked awfully intimidating to my halfling, so while she spoke with them, Shadowheart bludgeoned one to death. As long as Shadowheart attacked only the ogre with the dialogue icon over his head, her attacks never put her into combat nor broke the ogres out of the dialogue. I tested hitting a different ogre (one without the dialogue icon), and doing so broke the ogres out of dialogue and initiated combat.

Basically got a free kill with the ogres locked in dialogue.