Doubtful. She was around before Chapter 3. I think the trans girl only first appears in Chapter 3.
Well, we don't know about that either. If Ocean has defined all girls as females as canon, making one trans could be simply something he later included that potentially affects previous girls.
So, unless we have seen her naked, I don't think we can discard that many. That is, however, I doubt many of the one we have not seen naked are too. But who knows...
Speaking of WIAB, can anyone explain how the 2 stories are related? I've only starting following these 2 recently and all I can gather is that it's the same developer.
So far, I don't think we can. I get the feeling that the place in which WIAB's MC and sister have dinner is probably going to be the same place we are going now with Bella in SG.
But so far I don't think there has been anything explicit connection. I believe someone a few weeks ago did point out some surnames being shared now and there, specially in that high class restaurant but I don't remember that much.