I think Amelie is usable in the US.As for Maverick, I can't quite make up my mind about him. Sometimes I like it, sometimes I don't. Definitely usable and it doesn't strike me as particularly trendy.
Amelie is usable in the US, and I love the name. Maverick is a cowboy name to me, so I wouldn't use it. I definitely don't think these two names would work as a sibset, although I don't think you were asking about that.