Project HYPOSTAT-2 has been postponed indefinitely

The pure literal text we get is that Mizu was ~originally female and sometimes lives as male; in this a transmasculine reading presents itself from the literal stated circumstances if we assume that the framing of his initial gender assignment as diegetic is functionally "Mizu was AFAB", but interpreting it only slightly more allegorically a transfeminine reading presents itself

More specifically: Mizu was raised as a boy for safety reasons and continuing to present male into adulthood. He benefits from the assumption of his maleness, but this benefit is at best fraught and conditional; it is unavoidably complicated by that maleness existing in the context of her original femaleness. In his past, he tried to live by that femaleness, and managed actually to find a real happiness in that femaleness, but the fact of her femaleness was complicated too; the misogynist attitudes and actions of her husband served to prove that despite her happiness in a female role, she would be violently rejected from normative femaleness

Obviously here a nonbinary understanding also presents itself – Mizu cannot reject or uncomplicatedly accept either femaleness or maleness and both are meaningfully part of his identity. I would argue this understanding is actually essential given like everything abt Mizu as a character and the way her duality of identity in gender is inextricable from his duality of identity in ethnic positioning and in morality and that duality is Very Much What The Show Is About. But while a rejection of a transmasculine or transfeminine framing in favor of this is possible and meaningful, nonbinarity is not exclusive of transmasculine or transfeminine discourses, and it's entirely possible to situate Mizu in either or both while keeping this nonbinary understanding in mind