There are a lot of custom-made modifications for Sekiro's katana weapon all over the internet. But this mod is all you need, if you're looking for that one perfect Japanese sword, as it includes all of them in one convenient package.
Just select the one katana you like the best and put it into the hands of the Wolf. Just remember that this is purely a cosmetic mod and it doesn't influence the stats of your newly acquired weapon.
For other Sekiro: Shadows Die Twice guides, check out the links below: