I wouldn't use
Gracie as a full fn. As a nn for
Grace, yes, but never by itself.
If you want a two-syllable alternative to
Grace, how about
Gratia or
Graca? There's
Gracia and
Grazia, as well.
How about:
Grace MadelineGrace WinifredGrace VivianaGrace AbigailGrace JosephineGrace NicoleGrace MirandaGrace VirginiaGrace CatherineGrace Phoebe
Shannon