A special case, however, is lies
I can see a magical sword being dubbed "the Sword of Lies" by those who opposed it, or its wielder if it were not intelligent. Not by either the sword or its wielder. To be sure, a person is someone who lies, or at most who habitually lies, not someone who lies all the time, but what is the point of announcing yourself as a liar? (When you are not an entertainer.)
Sword of the Defense of Harmony, Preserver of Order, Defense of the Kingdom -- whatever the justification of the lies, call the sword after that.
'cause if someone told me something was a Sword of Lies, my reaction would be, "Is that true?"