When requesting a transfer to a certain club team, there are many factors which have the potential to decide the outcome.
However, the 2 most important ones are the following:
Firstly, your ability to fit into the team. Can you play in a position that suits their formation? Secondly, your capabilities. Are you good enough to start in the position they want you to play in? Unless your capabilities are good enough to at least earn you a place on their bench, then no club is going to want you.
If you are unable to play in the requested position, then it's best to learn in training.