I suggest using TOGO for this achievement. It is a 3 star team that should honestly be ranked higher. Togo has Emmanuel Adebayor who is an 85 striker and a powerhouse forward.
When I play, I use a 4 - 3 - 3 formation. For those who recommend playing a 5 - 4 - 1 and waiting for an opportunity, I advise against it, at least for this team. Togo is extremely good at give-and-goes and through balls. You can also use a 4 - 4 - 2 if you are a more defensive person. As long as you have at least two players up front so that you can work with give-and-goes, then you should be fine. After going up two, or maybe just one goal, then I would switch to a more defensive formation like 5 - 3 - 2.
As for winning each game, I have four major pointers:
1) Use give-and-goes... a lot. It's remarkable how many players defend holding the buttons A + B. With this type of defending, two defenders will pull on to one guy, leaving a clear space in front for a give-and-go through ball. When done correctly, this can lead to an easy pass and shoot goal or a simple finesse shot (RB + B).
2) This leads to my second piece of advice. DO NOT defend using A + B, or even just A for that matter. Only really hold the A button when the other team is pushing towards goal on a breakaway or there is a loose ball. I strongly recommend defending using LT + B. Holding B will make a defender pressure the ball dribbler. Holding LT allows you to control an idle player and essentially cover passing lanes and open ground. When done correctly after some practice, you will be able to prevent the other team from scoring pretty easily. The other guy will usually push forward with passes and the player you control with LT will allow you to steal these passes.
3) Use finesse shots (RB + B) when moving from the side of the field towards goal. With practice, you'll be able to perfect your shooting so that you can score from 25+ yards out with finesse. Also, if you follow my first piece of advice and use give-and-goes, you will most likely get opportunities where you have a break away from 40 yards out and the other team pulls their keeper all the way out. In this case, finesse the ball!!! It will be an automatic goal almost every time. The ball will curve around the goalie and land essentially in the middle of their goal. The amount of power really doesn't matter that much here if you finesse it.
4) DO NOT sprint all the time. Some players will sprint every time that they get the ball. I strongly recommend not doing this. You should sprint and dribble when you have open space and can move the ball forward safely. And if you are going to do this, dribble away from their players. I recommend just dribbling normally, this means without sprinting and without slowing yourself down holding LT. If you just dribble at a normal speed, use the LB button to cut the ball and back-and-forth in order to weave through the other team. For those who have never done this before, you'll be surprised how easy it is to dribble through the other team's defense when you control the ball and they are sprinting past you.
If you follow these pointers and use Togo, you can easily make it into the latter rounds of the tournament every time. Good luck winning the tournament!