I absolutely adore the name [name]Sasha[/name]/[name]Sascha[/name] for a boy but am not sure about the spelling. For some reason [name]Sascha[/name] reads more masculine to me, while [name]Sasha[/name] seems a bit more unisex. Any opinions?
I know a male [name]Sasa[/name], (Meaning, origin and history of the name Saša - Behind the Name) pronunced the same way as [name]Sasha[/name]/[name]Sascha[/name], for a boy I think I prefer [name]Sasha[/name] still, the c spelling makes it a bit awkward in my opinion! Though I feel there is a fourth spelling that I am forgetting!
However you spell it, [name]Sasha[/name] was more unisex but with one of the first daughters having it for a nickname, it’s become more feminine perhaps.
[name]Sascha[/name] looks more masculine and less nicknamey
I like [name]Sascha[/name] a lot better.
I like [name]Sascha[/name] better for a boy.
What about [name]Sacha[/name]? Personally, I like [name]Sasha[/name] better because [name]Sascha[/name] looks too frilly with the extra ‘c’.
I’ve only known female Sashas, but my old school teacher was male and called [name]Sacha[/name], so [name]Sacha[/name]/[name]Sascha[/name] seems more masculine to me. He told us once that his family came from eastern Europe somewhere, if that makes a difference 
[name]Sascha[/name] is the [name]German[/name] spelling and [name]Sasha[/name] is the Russian* spelling. Neither is more masculine or feminine than the other.
*English Russian spelling… you know what I mean.
I think sasha is easier to spell and won’t be misspelled, whereas [name]Sascha[/name] looks cool, but would be constantly mispronounced and misspelled. Renrose is right, though, neither is more masculine or more femenine.
I think It sounds better on a boy, personally, so I like that you are considering it!