Meh. I am as bothered about this as I am about history from a modern feminists/class/socialist/whatever perspective. Using historical figures to explore whatever ideology is what some academics do- and I say that as a very run of the mill historian. Exploring J Of A and Elizabeth I from a trans perspective is to be expected. You don't have to buy into it.
In my opinion Joan of Arc is not particularly a heroine and her story has been rewritten a million times. She is what modern people want her to be -pious saint, religious fundamentalist, mentally ill teenager, feminist icon, pawn of the patriarchy. It's what some historians do. And this isn't even history its a made up play.
However I agree with this
@DameHelena If this production existed in a cultural moment where this debate was not so present and so hotly argued, I'd probably feel more charitable towards it. In its context though (as someone points out, the whole cast has declared their pronouns and the writer is self-declared non-binary), it cannot seem like anything other than a cynical exercise in stirring up controversy and titillating those who are titillated by stuff like this (reference the promo image of a clearly female and young person in ye olde version of a chest-binder).