A word for someone who is left-footed but right-handed

The terms cross-dominance, mixed dominance, mixed laterality, hand-confusion, and mixed-handedness are used to describe the use of different sides of the body for different things. Fans of board-sports might also be familiar with goofy-footedness.

In other words, the original poster could be described as cross-dominant.

Don't have a big issue with the accepted answer.

However, from personal experience, handedness in soccer (sorry for being an American here) is a bit different than when using actual hands.

I'm a lefty, but after a couple of years of play, I discovered that while I have more control with the left foot, I have more power with the right. Thus I'd usually shoot or clear a ball with my right, unless I'm going for placement (eg: an inside or outside of the foot shot). Dribbling is done with both feet. A player who never touches the ball with one foot is probably not a very good player.