ok, I know I am not in my 50s, but I think it should well be possible for people to 'pass' even those going through this in their 50s. It really depends how your body type as it is now, hight ? - not so much, locally where I live, we got 6 foot girls - yes they are totally, natal females. But very slim/slender. If your like a burly looking guy in his 50's with a lot of muscle tone, I would say it would be a "challenge" for you. If we allow ourselves to stereotype, ourselves trying to 'fit' into what society expects us to look like, I think we would all be running around endlessly trying to look like something, and some one else. Really need more info about you though, otherwise, I think advise is going to be vague at best. If you got no chance right now, I think hormones first, then see how you start to look in another 12 months, change you diet, exercise, do not do any though that adds body bulk/mass, consider exercise that helps reduce body fat, etc.