With regard to passing, facial features that are at least androgynous are necessary but not sufficient. That is, when your face is sufficiently feminine or androgynous, people will look (whether consciously or subconsciously) to other cues, like facial hair, head hair, shoulder width, breasts, hip width, hand size and shape, foot size, and gender presentation and expression.
This is why, for many with masculinized facial features but otherwise acceptably female presentation and body metrics find that FFS is able to turn the tide of passing around.