score:5
Not 100% certain and no idea of the time period or authenticity, but FWIW the blade's slightly bent shape that grows thicker towards the end of the blade, pointy tip, and the grip's slight curve make it look more like a Chinese style saber (with an unusual looking guard) than a katana:
Here's a typical Katana schema for comparison. Notice the characteristic shape of the tip, how the blade has a regular thickness, and the straight, lengthy grip that allows for two handed usage. It contrasts with your blade's pointy tip, it's slightly larger thickness towards the end of the blade, and the slightly bent single-handed grip: