Make a sword which increases chance of beheading?

[KhajitDave]

I want to make this for a mod, but as I'm a modding beginner, I don't know how.

 

If it's possible, please tell me how to do it.

Also, can I make this sword work even if you haven't unlocked the beheading perk? I'd like this sword to be available to use from the very beginning of the game.

 

Thanks a lot!