Install with any mod manager or extract contents to data folder and activate the .esp.

To get the sword in game, type in console:

"help bigsword 0" for the onehanded Id

or

help"great saber" 0" for the twohanded Id

then type

"player.additem id" (id is the one you just got)

PS The downloaded read me is wrong for the two handed ID. The online read me so correct.



Credits
 cnyylzy123456789 for the sword model for Skyrim

 invalidfate for making it available to Fallout 4 as a sledgehammer replacement

BOTLANNER for making it a standalone weapon(doesn't replace sledgehammer anymore)