Problem is already solved with FFXIV....

You create a character and if you actually feel like M or F.. you can create that and act like that and be like that... whatever way of how you are mentioned, as in real life, you need to either tell people, or tell on which way you sway, so they can ask.

the most polite way is always to call people the their chosen name, and that is all what there can be said about that.