Copy and past the katana folder into:
Grand Theft Auto V\mods\update\x64\dlcpacks
Now open OpenIV and go to this location.
Now paste this line dlcpacks:\katana inside dlclist.xml
Load the game. use Simple trainer by sjaak.
weapons – Spawn weapon by model name.
Warning: Don’t search-buy it from shop!! Also don’t buy other weapons from shop as long as you use this addon weapon!!
Model converted to grand theft auto V by: Sandra Linson
Model created by: BlackBradHz
Database created by: yeahhmonkey