Given that Heroes’ localization updated Kyza from Radiant Dawn as a non-binary character, I often think about how they are treated in Japanese Heroes and if it differs at all from their portrayal in the Japanese Radiant Dawn. I haven’t been able to find any concrete answers online, so I would greatly appreciate it if you could look into the matter.
In my conclusion and TLDR, Kyza is definitively portrayed the same in JP Heroes as they were in JP Radiant Dawn.
I first checked Kyza’s JP “Meet some of the Heroes” entry on the official FE Heroes website (link here), and sure enough they are referred to by name repeatedly, and no pronouns are used. This is very common in Japanese. The most notable thing here is that they are described as having the heart of a maiden (乙女心, otomegokoro), but this word doesn’t describe a female character necessarily - it describes a pure heart/ love, like that of a teenage girl or young woman. Leon and his feelings for Valbar are also described in the same way in Echoes.
After that, I compared most of Kyza’s text in Radiant Dawn vs Heroes - not a hard thing to do when they are from one of the FE games with the least amount of development for each individual character. Their speaking is still the same - ‘standard polite’ Japanese when first talking to the Summoner, then once their casual side slips out, like in their lv. 40 convo with the Summoner, they use atashi as their ‘I’ pronoun, which is normally used only by girls/ women.
Using atashi as their ‘I’ pronoun is pretty damning evidence that some kind of gender fluidity is going on, but I knew there was something deeper I could probably find. I wanted to see if I could get an official source listing them as ‘male’ or ‘female’ outright.
In the end, I did not get an official source, even the Radiant Dawn art book does not list gender in the character bios. But the fan entry on @Wiki does list them as male, otoko specifically (link here). While the Wiki entry was originally written during the Radiant Dawn era, it was updated after Kyza was added to Heroes.
The Pegasus Knight Wiki also describes them using the kare male 3rd person pronoun, and as an ‘onee’ character (link here). This comes from the word for big sister, and is a trope describing a male character that uses feminine gendered language.
And that’s everything that I found! Considering that Japanese gendered language does not translate directly into English, I agree that writing Kyza to be non-binary was the most straightforward way to convey their gender fluidity. Especially when Kyza gets so little room for development on-screen.
