I say it trisyllabicly, though I say
Margaret disyllably because for some reason, in my accent it's difficult for me to pronounce that name otherwise -- makes it difficult to make the nasal schwa at the end. Ingaret I don't have a problem enunciating though.
Ooh I really like some of these.
Edith,
Helen,
Hester,
Mabel,
Mary,
Sophie, and
Tamsin are great with it. Thank you!