Good luck “trying on” the names!
For both [name_f]Susanna[/name_f] and [name_f]Rosanna[/name_f], you could use [name_f]Sanne[/name_f] (SAN-eh). I love [name_f]Rosanna[/name_f] and would be thrilled to meet one.
[name_f]Emilia[/name_f] is unfamiliar enough that you could perhaps get away with insisting on a new pronounciation—I’ve known Emilias who said [name_f]Emma[/name_f]-leah, [name_f]Amelia[/name_f], and Eh-MILL-ee-a. So E-mel-e-a is plausible! 
I like all the names ([name_f]Rosanna[/name_f] is my favorite) but have you considered taking all three with you and deciding after you see her? My mother, aunts, and older sister all took a few names with them to the hospital and decided after seeing the baby. They used that method with all of the children except one, who was named for a recently passed family member - so that’s twelve children total. It turned out pretty well for us. Plus, it may help to sway your boys into loving [name_f]Violetta[/name_f] if she comes out and her face just says [name_f]Vi[/name_f].