You really should just scroll through all the maggie dresses, it won't take you too long and you might find a style that you really like. She has a lot that have Belle elements, so it depends on what you like best about belle's dress. Is it the skirt, the off shoulder sleeves, the bodice...etc.
To get you started, I thought the Capri (all variations), Brittanya, Emme, Brielle, Maeleigh, McCall and Victoriana were very Belle-like, I was focused mainly on the skirt.
Addison has Belle like sleeves. But there were a bunch of other dresses that had Belle like skirts, a few that had sleeves like Belle and some that had bodices like Belle's. Depends on how literal you want to go with it.