To get this trophy, you'll need to throw diamonds at another player. This can be a local player (both on the same console) or an online player. If you don't have Playstation Plus or another controller, then there is another method which will allow you to get this trophy anyway. Keep in mind this method only works on the old Editions version of Minecraft PS4, and you'll need two accounts to pull this off.
On the account you want the trophy on, hold down the PS Button on your controller and open the Quick Menu. Go down to Power, and select Switch User. Switch to your other account, and then open Minecraft. Press X once, and you should see a dialog box telling you to "Press X to join". Do it, and you should enter split screen mode, with your controller controlling the second player. Go to Switch User again, and switch back to your main account. With your diamond in your hand, walk up to the second player in game, and throw them the diamond. If done right, the trophy will pop.