@TatianaBis
Sylvie and Elodie are French, Cosima is Italian and Ottilie is German and French. Why are Italian and German names more try hard than French and trying hard to be what precisely?
Nothing to do with the origin of the names - more to do with familiarity I think. Both Cosima and Ottilie are very unusual names without being particularly pleasant sounding (to my ears at least), which gives me the impression, rightly or wrongly, that the name is being chosen more in an attempt to be 'unique'. I wouldn't actually choose Elodie myself, but Sylvie is quite sweet and much more familiar due to the use of Sylvia (which I actually think is much nicer). It's really just a personal opinion, which is what the OP asked for. Other people who like the way the name sounds will obviously form a completely different opinion, but to me, Ottilie sounds quite harsh and clunky. It would be very dull if we all liked the same names