I think both names might be a bit marmite tbh, OP.
When I hear Maud, I think of Maud from the Worst Witch books - wasn’t she terribly slow and “plump” and generally viewed dull and uninteresting poor thing? Maudie does sound sweet. Maud will forever sound lumpish to my ears.
Mary - I will confess a vested interest in this name (And I’ve name changed accordingly!). I am a mid 30 year old of this name and detested it growing up. I still think about shaking it off. It only shortens to Maz/Maza which is deplorable imo. Every job I start I think I’ll change to my middle name but never get round to it. I really don’t think of myself as a Mary, I’ve really struggled with identifying with this name.
On the flip side, everyone I meet does seem to like it and be surprised / intrigued I’m the age I am with this name. I enjoyed meeting a 5 year old Mary the other day.