I’m not in Australia so I’m not sure what names are dated to/were popular in the 90s there, but here are some names that I would consider offbeat classics, and seem like your style (based on the names in your signature:
[name_f]Cosima[/name_f] - [name_m]Coz[/name_m]/[name_m]Cos[/name_m], Cosi, [name_f]Mimi[/name_f]
[name_f]Jessamine[/name_f] - [name_u]Jess[/name_u], [name_f]Jessa[/name_f], [name_f]Minnie[/name_f], [name_f]Mina[/name_f]
[name_f]Caroline[/name_f] - [name_f]Cara[/name_f], [name_u]Caro[/name_u], [name_f]Carly[/name_f], [name_f]Lina[/name_f]
[name_f]Vivienne[/name_f] - [name_f]Viv[/name_f], [name_f]Vivi[/name_f]
[name_f]Saskia[/name_f] - Sassy, [name_f]Kiki[/name_f]
[name_f]Rowena[/name_f] - [name_f]Ro[/name_f], [name_u]Roni[/name_u]
[name_f]Marianne[/name_f] - [name_f]Mari[/name_f], [name_f]Annie[/name_f]
[name_f]Eveline[/name_f] - [name_f]Eve[/name_f], [name_f]Evie[/name_f], [name_f]Lina[/name_f]
[name_f]Fiona[/name_f] - [name_u]Fee[/name_u]
[name_f]Cecily[/name_f] - [name_f]Cece[/name_f], Ceci (sess-ee)
[name_f]Giselle[/name_f]/[name_f]Gisele[/name_f] - [name_f]Gigi[/name_f], [name_f]Elle[/name_f], [name_f]Ellie[/name_f]
[name_f]Florence[/name_f] - Flee, [name_f]Flo[/name_f], [name_f]Flora[/name_f], [name_u]Ren[/name_u]
[name_f]Georgina[/name_f] - [name_f]Gigi[/name_f], [name_u]Georgie[/name_u], [name_m]George[/name_m], [name_f]Gia[/name_f]
[name_f]Christabel/name_f - [name_u]Chris[/name_u], [name_f]Chrissie[/name_f], [name_f]Christa[/name_f], [name_u]Abby[/name_u], [name_f]Belle[/name_f], [name_f]Elle[/name_f], [name_f]Ellie[/name_f]
[name_f]Lydia[/name_f] - Liddy, [name_f]Lili[/name_f] (lee-lee or [name_f]Lily[/name_f]), [name_f]Dee[/name_f]
[name_f]Matilda[/name_f] - [name_u]Mattie[/name_u], [name_f]Tilly[/name_f], [name_f]Tilda[/name_f], [name_f]Milly[/name_f]
[name_f]Gwendolyn[/name_f]/[name_f]Gwendolen[/name_f] - [name_f]Gwen[/name_f], [name_f]Dolly[/name_f], [name_f]Wendy[/name_f], [name_u]Lyn[/name_u]
[name_f]Ginevra[/name_f] - [name_f]Ginny[/name_f], [name_f]Gigi[/name_f], [name_f]Evie[/name_f], [name_f]Eva[/name_f]
[name_f]Helena[/name_f] - [name_f]Elle[/name_f], [name_f]Ellie[/name_f], [name_f]Ella[/name_f], [name_m]Len[/name_m], [name_f]Lena[/name_f]
[name_f]Beatrix[/name_f]/[name_f]Beatrice[/name_f] - [name_f]Bea[/name_f] (bee or bee-ah)/[name_f]Bee[/name_f], [name_f]Trix[/name_f], [name_f]Trixie[/name_f]
Not three syllables:
[name_f]Araminta[/name_f] - [name_u]Ari[/name_u], [name_f]Minty[/name_f], [name_f]Minnie[/name_f]
[name_f]Emilia[/name_f] - [name_f]Em[/name_f], [name_f]Emmy[/name_f], [name_f]Milly[/name_f], [name_f]Mila[/name_f], [name_f]Lia[/name_f]
[name_f]Lenore[/name_f] - [name_f]Leni[/name_f], [name_f]Nora[/name_f]
[name_f]Theodora[/name_f] - [name_f]Thea[/name_f], [name_u]Theo[/name_u], [name_f]Dora[/name_f]
[name_f]Phoebe[/name_f] - [name_u]Fee[/name_u], [name_f]Bee[/name_f]
[name_f]Lucille[/name_f] - [name_f]Lu[/name_f], [name_f]Lulu[/name_f], [name_f]Lucy[/name_f], [name_f]Cilla[/name_f]
And seconding [name_f]Penelope[/name_f], [name_f]Clementine[/name_f] and [name_f]Bryony[/name_f], also gorgeous names!