To unlock the 2nd Rounder trophy in Madden NFL 19, you will need to score a game-winning field goal with 10 seconds or under left on the left on the clock after missing 2+ previous field goal or conversions.
The easiest way to do this is to play with two controllers. Play two minute quarters.
During the first half, whenever your second controller (the one not unlocking the trophy) has the ball, select punt and whenever your main controller (the one going for the trophy) has the ball select field goal.
In the second half, you should have easily have missed two field goal attempts already. Make sure your main account has the ball and take your time progressing down the field until you are in field goal range. Run the clock down to under 10 seconds, take a time out to give you a little bit more time and then score the field goal to win the game and unlock the trophy.