Playing piano by ear is something that some people do right from the start. They learn this way and most often than not they will find it difficult to play by reading music or even chord sheets.
Others start to learn piano playing by reading music, a lot of these people find it equally as difficult to play anything with out the music in fromt of them.
The best scenario is when you learn right from the start how to play by ear and how to read music both at the same time. Don’t choose any one method but learn how to play the piano by ear and also learn how to read music. You will benefit greatly in the long run by doing this.