"... IPSO guidance which is to refer to trans people using their preferred identity ..."
Where does IPSO say this? Not in the link posted above, as far as I can see. However, it does say:
An individual’s gender identity and sexual orientation must not be referenced unless genuinely relevant to the story.
But doesn't that mean that the person in this story must not be referred to as a woman, since that can only be a reference to the person's gender identity?
Also:
Clause 1 (Accuracy) requires that the press must take care not to publish inaccurate, misleading or distorted information or images.
If describing this person as a woman or as female is not understood as a reference to the person's gender identity, then it would have to refer to the person's sex, in which case it would be both inaccurate and misleading.
Or am I missing something?