What are the best transferable competences for top management positions?

This is not a straight forward. Throughout your career life, you gain knowledge and skills and will be able to shape your attitude which altogether build your competencies. The positions you held play a major role in the type of competencies you gain and therefore the career path you chose will require certain competencies. Not to forget that there are function related competencies and some general or core competencies  

If you are in a Finance career path; starting as Junior Accountant and heading up all the way to a Finance Manager or even CFO, your function related competencies will be mainly focusing on what you need to perform such duties. On the side, you will need general competencies to help you in being able to advance throughout your career.