Making a fake rare blade is basically just copying the data of the rare blade into a common blade
BLACK
Scroll down to find the common blades
Yellow
Must make sure the Race, Gender and Still are the same with the rare blade you copying with as it affects the characters Menu
Feel free to add or change the element but its more preferably if your Element match your Rare Blade
BLUE
Feel free edit stat! Make it OP
Orange
Copy the rare blades weapon -note that i haven't got an how to change the weapon model so this kind thing works with unique weapons like SHULK and FIORA
Green
Just put the rare blades name and leave the common blade name
RED!
DON'T EVEN TRY TO EDIT IT!
Copy Specials from the rareblade as it affects the animation (im not sure what would happen if you didn't)
Feel free to edit the Blade arts
Make sure you copied Resource Data Fully
And the Other Data too
Feel free to edit Field Skills and Battle Skills
Here is an example of Common Blade [Fiora]