Obviously, go to Retro mode, choose your opponent to be a Double-A team, set them as the home team. Choose your team to be an All-Star team, move any better power hitters into the starting lineup and order them in the lineup from best to worst. Set hitting difficulty to beginner. Keep hitting until you get the trophy or until the 1st inning ends. If you don't get it by the end of the 1st inning restart so you can hit again right away.
Alternatively, if you have not yet unlocked "Still got it" and/or "Back in time", turn on the 8-bit filter for "Back in time" and keep playing until the end of the game instead of restarting if you do not get this trophy in the first inning. You should most likely get it by the end of the game.