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A person with an object that allows them to discern the truth could still be considered a Living Lie Detector under the "...may be the effect of some Applied Phlebotinum" portion.
The latter half there, if it forces someone to tell the truth, seems to be covered by Truth Serums. (Some of the most famous examples, like Wonder Woman's lasso, are already there.) For the other variations (forces them to be good, evil, etc.), could be something like Artifact Domination or Weapon Wields You depending on the circumstances.

Instead of being a living lie detector, or a person who always tells the truth, it's an object. Like the aletiometer in "His Dark Materials". Alternatively, in a more generic sense, an object who has magical properties which drives the person wielding it to do, say, or have certain qualities, like increasing goodwill, evil, or always tell a lie.
Edited by luigirovatti