Notes:

I was found on Smash Ultimate Hell, but, this is an edit of cuboon's Summer Fermale Byleth concept art, and the source from the edited concept is unknown. Meme made by RickRollMaster (please find the original sauce by entering on his Twitter profile)

Let's imagine about the International version of Summer Byleth, she wears a black sportswear for women-like swimsuit, while the original Japanese version, she still wearing bikini.

Original unofficial Summer Byleth "International" version image by dynamaxine

And why Fire Emblem Heroes doesn't have regional diference? It's very weird Fire Emblem Heroes isn't censored in the International version, because, some video games were censored such like sexual content, religious content, drugs and alcohol use, violent content, etc.