You simply need to defeat 1 of each enemy in each level as Futo.
Make a point of whenever you start each level to use him straight away and defeat 1 enemy!
If you do miss an enemy you can use the level select to travel to each level and get an enemy, as this trophy doesn't need to be done in 1 playthrough.
A level that you potentially have missed him on if this hasn't unlocked his Snowy Canyon!