The Red Threads of Fortune is the second novella in J.Y. Yang’s Tensorate silkpunk fantasy series about a set of twins, Akeha and Mokoya, who are born to the Protector of a kingdom (their mother), who gives them away to a monastery to settle a bargain. Later, their mother takes back on of the twins, Mokoya, who had developed prophetic powers. The series celebrates gender diversity and in its world characters choose the gender they associate with at a certain age, so children are often referred to using the gender-neutral pronoun “they.”
This is all introduced in the first novella, The Black Tides of Heaven, which focuses on Akeha. The events in The Red Threads of Fortune picks up some months (I think) after the end of The Black Tides of Heaven and focuses on Mokoya.