Margaret, in English, has a long and distinguished history and a variety of nicknames to suit every taste.
Margot, in French, is no doubt fine.
Margot, in English, is a recent arrival with a pleasant association with
Margot Fonteyn - but that was a stage name, picked because it was exotic. Not being French, or in need of a stage name, I wouldn't like being a
Margot, though I'd be a
Margaret quite happily.