I'm not big on masculine nicknames on girls, but I do like:
Toni for
Antonella/
AntoniaHarry for
HarrietAndy for
AndreaDani for
Daniella/
Danika
These names are unisex, but I consider them feminine. I do think they sound great on boys though:
LindseyQuinnFrancis (
Francis is very masculine to me, but
Frances is what I think of first when I hear it)
Casey (this one is pretty evenly split between masculine and feminine for me actually)