I have a cousin named [name_f]Sofia[/name_f] (middle name [name_f]Belle[/name_f]) who doesn’t like having a name that is extremely popular at her school (except the others probably spell it [name_f]Sophia[/name_f]). So, she mentioned wanting to go by something different next year when she enters high school. I thought I’d pop on here and see if y’all have some good ideas for something different for her to go by. Oh, and I suggested [name_f]Sofie[/name_f], but she strongly disliked that!
[name_f]Effie[/name_f] and [name_f]Fifi[/name_f] are cute as well as the PP’s suggestions. 
I once babysat a little girl named [name_f]Sofia[/name_f]. She went by [name_f]Fia[/name_f] or Fifa which I though was really cool! Her brother would also call her Fi ([name_u]Fee[/name_u]) on occasion.
I like the suggestion of [name_f]Fia[/name_f]! [name_f]Sia[/name_f] would also be a nice option.
[name_f]Fia[/name_f] is a great option! It is distinctive, but has the same cosmopolitan and sophisticated vibe of [name_f]Sofia[/name_f].
[name_f]Fia[/name_f] is a good option
[name_f]Belle[/name_f], [name_m]Seb[/name_m], [name_f]Sosie[/name_f], [name_u]Fee[/name_u], [name_m]Sol[/name_m], [name_f]Febe[/name_f], [name_u]Scout[/name_u], [name_f]Bee[/name_f], SB, [name_f]Essie[/name_f], [name_f]Sibelle[/name_f]/Sibil, Sassy, [name_f]Sisi[/name_f], [name_f]Sable[/name_f], [name_u]Fable[/name_u]
[name_m]How[/name_m] about [name_f]Sonia[/name_f]? In Russian culture it’s the standard nickname for [name_f]Sofia[/name_f].
[name_f]Solene[/name_f] came to mind.
[name_f]Safia[/name_f]/Safya
[name_f]Sia[/name_f]/Sya
[name_f]Fia[/name_f]
Anasofia
Soana
[name_u]Fee[/name_u] Or Opie maybe [name_f]Sia[/name_f] is also a possibility.
I second [name_f]Sosie[/name_f]