Tired of looking for this, who is the Sleeping Dragons cameo?

I can't answer you're primary question; but Shepard's gender is referenced at least once in an unlocked memory, I believe.

Localization presumably, not all languages allow gender-neutral references, you know.

The bro/femshep choice may be for flavor/shaping your story, like a lot of the DA Keep choices. I don't remember a gender reference either (they did the same thing for Shepard in the books). It's possible for DLC, I guess. It would be cool to hear Shepard's voice again in a recording.

It may make a difference in German. But I don't play the German version, since the VAs are cringeworthy. I only watched a few youtubes with the German localization, but they were enough to not make use of it. Emotionless deliveries, as if they just read it from a sheet of paper someone just shoved under their noses.

On a side note and from the top of my head, remembering how the Shepard referrences were delivered, I doubt that there's a real difference. You could gender the rank, but that's unlikely, since english military ranks usually aren't translated. Commander stays Commander. And that's about the only opportunity to gender - far as I remember anyway. Shepard is never adressed as he or she. Just as Shepard or Commander. And that would be the same in German.

The game guides have been known to have errors printed before: I recall similar confusion to yours about certain things in the past with other games. Apparently there is also sometimes a poor choice of words that lead to misinterpretation and misunderstandings. I'm sorry if you had your hopes up because of it.