Is it possible to make a sugar bottle in the shape of a champagne bottle? I've seen them done for beer bottles, but nothing else.
Yes, you just have to make a mold for it first.
Yes check the how to make a sugar beer bottle video tutorial. You would need to use a bigger tube and more of the mold stuff... I bet the MakeYourOwn molds guy MYOM-Dominick would have your answers. He is so helpful, Here is the link.