Vinland Saga

[KrayZ33]

I'm more or less not seeing it because Canute as a girl would make no sense.

In Fate, King Arthur being a girl pretending to be a man made sense because they were in need of a man holding the crown for stability etc. etc.

But here? "He's" the second in line, the King has no need for a weak successor and it would only hurt the kingdom.
How or with whom would he switch places anyway? Unless he has a twin sister and it's her we are seeing right now, it wouldn't be possible. After all, the hair doesn't grow over night and in the end he'd still look like a girl.