I think both are really nice and I've been thinking about them a lot lately myself. At the moment I prefer Eden though.
I think they could work for sisters names, they start with the same letter, but they do end in different sounds.
Eden and Michaela / Esme and Brianna
Esme Tallulah, Esme Charlotte, Esme Lillian, Esme Olivia, Esme Lucinda, Esme Violet, Esme Rachel, Esme Rhiannon, Esme Alexandra