So, the prerequisite down at the bottom of the card, say Machete, is that just to use the Cleave trait, or all the traits, or the whole card in general?
Just for section it is in , so Cleave . I think Walter confirmed this and if you look through cards you will see a pattern where this wouldn't make sense otherwise.
Look at 32 CAL Revolver
Its Bash prerequisite has melee 3 but it is a firearm so it wouldn't make sense to fire it you would need a high melee skill but does make sense to use it as an effective melee weapon takes melee skill.
Hope this helps.