I like [name_m]Spencer[/name_m] for a girl, especially in a US context where you pronounce that R and have a history of boy names for girls and last name-names generally. It’s a zippy and fun name while also being preppy and smart.
I like [name_m]Spencer[/name_m] [name_f]Elisabeth[/name_f] - S over Z for [name_m]Spencer[/name_m].
An elegant combo!