Pretty simple trophy to get and a big clue is in the trophy title. When you get the bow ability, simply shoot the shield enemy in the open space at the top of the shield. You can make it quite easy with an upgrade on the bow that slows down time.
It can be done earlier with some luck, either jumping over the enemy & landing a heavy strike from behind or in one of the battles when you can form a rot snake monster & do the R2 slam.