As title really. Rather than being captured and executed, what if she lives to a ripe old age?
Could she have been a Late-Period Crusader? I quite simply love the idea of an adult Joan of Arc being involved in a relief campaign for the Byzantines, even an advocate for them once the Emperor Constantine converts.
So I guess my questions are twofold.
1) What do you think would happen if she lived?
2) Regardless of your answer for one, assuming events organise themselves so that Joan of Arc gets herself involved in the 'Rescue of the Romans' upon some unsettling coincidence where she arrives in court as the news of the Coronation of Mehmed II reaches Paris? Could she have the pull/power/popularity to organise a large crusade on so short a notice?
(I know this is odd, but I do find the idea of the Romans being saved by the Maid of Orleans devastatingly romantic.)