Bridesmaid body shapes

Sorry for the title I dodnt know what to put


We have 2 adult bridesmaids one who is tall and slim and the other average height but quite an apple shape with big bust.
Her mum has told me not to let her have any say in the dress as she has no idea what suits her and I am finding that to be true.
I showed her some bridesmaids dresses that I thought would be very flattering but she keeps sending back exactly what I would avoid!
I even sent images of those multi way dresses and she said oh yes I would want mine like this (the skimpiest more unflattering way)
Do you think a V neck drop down under the bust would be flattering for them both? She wore a beautiful off the shoulder dress last time she was a bridesmaid but our other bridesmaid doesnt want off the shoulder (I would like them matching as there are only 2 of them, if there were 3+ I could probably get on board with same colour different styles but not for just 2)