These where designed for vanilla "weapon3". If you access your game/img/system. There is a "Weapons3" image. You can only have 6 additional weapon images in the base game, right now you'll see a book. If you want to rename that and drop this image in there called "Weapons3" it will give you 3 Chinese weapons as undefined 1, 2, and 3.
These are accessed in rpg maker mv via system, then you'll see a section for weapons. You can change the image or add a new one.
Feel free to use this however you want, other plugins or vanilla with commercial and non-commercial games. Please credit me though.