I'm not familiar with
Bayard. I'd say it "BAY-erd," almost one syllable actually, if I came across it. But regardless, I dislike it. It just doesn't sound like a name to me.
Sacha I do like, particularly as a nickname for
Alexander. I'm not sure if I would ever be bold enough to use it, but a little boy named Sacha/Sasha would be adorable.