A pretty cool looking high tech katana blade. This sword mod comes in a 1 handed and a 2 handed version. Go check it out if you're into melee weapons over firearms!
Here is another Fallout 4 weapon mod for those who love katana blades. This melee weapon mod is called the AE-86 Seiryuu Beam Katana. The link to this weapon mod for Fallout 4 is listed below.
Credit goes to 0Theara for creating this cool looking katana blade.