Cooldown applies to every *specified* item

Status
Works as designed
Issue description

I am not too certain if this is a bug or not, but whenever i activate the cooldown for my custom sword in my main hand, it applies to the same swords that are not in use, including the ones in the creative tab as well. 

I am not very experienced with other methods, so if there is a better way to apply this, it would be much appreciated.

 

Issue comments

This is how vanilla cooldown works. For more advanced cooldown, you might need to make a timer and store timer values in NBT.