Does Dirk know their Sword is a Fake?

The type of sword Dirk uses (the sort of straight edge katana) is actually a type of ninja sword (called the Ninjatō, which you can look up to see what I'm saying being true) that was invented in the 20th century (19XX). Like, there's no historical evidence that the Japanese even used this sword type, or how even to use it, since it was basically made up maybe?

So did Dirk know this, and used it "ironically" or what?

Furthermore, do you think Hussie knew about this, if Dirk didn't?

Personally, I have no idea.