I wasn’t quite sure what style you wanted, so I took names from all different cultures in Europe, because that seemed to fit. Hope you find some you like!
Girl:
Linnea / Linnéa (Lin, Nia)
Sunniva (Siv, Sun, Suni/Sunny, Niv/Neve, Iva)
Elisedd (Elli, Ellis, Elise, Sedd, Sedda, Liese/Liz)
Godiva (Div)
Hildegarde (Hilda, Hil, Gard)
Wendelin (Wend, Wendy, Dellie, Della, Lin, Enda, Wenda)
Isolda/Isolde (Isa, Issi, Sol, Sola)
Nimue (Nim, Wae)
Apolena (Lena, Ap, Pol)
Elizaveta (Veta, Liza, Eliza, Ella, Avi)
Helena (Lena, Elen)
Adelheid/Adelaide (Del, Della, Aleida, Laide)
Diantha (Ann/e, Dia, Antha, Diane, Diana)
Jacintha (Cintha, Jace)
Jolanda (Landa, Jola)
Katinka (Tink, Tina, Kat, Katine)
Marina (Mar, Rina)
Mariska (Mar, Risa, Riska, Rika, Aris)
Saskia (Kia, Askia, Aska)
Dorothea (Thea, Dora)
Elvira (Vira, Elva)
Esteri (Tera, Essa)
Kaleva (Kale, Ale, Eva, Leva)
Sakari (Kara, Kari)
Sinikka (Nika)
Aislin/Aisling (Lin, Ash)
Chiara/Ciara/Kiara (Key, Ari, Ara, Kia)
Muriel (Riel, Mura)
Noreen (Rina, Nora)
Nolwen (Nola, Wenna)
Siobhan (Vonna, Sha)
Catriona (Tria, Ona, Catri)
Fenna (Fen)
Fianna (Fia, Fina, Anna)
Fionnuala (Fin, Nala, Nola, Nuala, Finna)
Leocadia (Dia, Leah)
Seraphina (Fina, Sera)
Svetlana (Lana, Sveta)
Milada (Mila)
Nikola (Nika, Kola)
Oriana (Ori, Ranna, Ria)
Magdalena (Lena, Dala, Dale, Mags, Magda)
Aurelia (Lia, Aura, Rel, Relia)
Elowen (Wenna, Ella/Ela, Loa)
Luminita (Lumi, Mina, Nita)
Elsinore/Elsinora (Nor, Nora, Elsa, Elisa, Elsi,)
Claudia (Dee, Lauda, Cloud)
Alys (Lys, Al)
Liesel (Liese)
Briallen (Bria, Bree, Alla, Allen)
Ceridwen (Wenna, Rida, Cera)
Eluned (Luna, Eluna, Lunet)
Rhiannon (Ria, Anna)
Eirlys (Eira, Lys)
Gwenyth/Gwyneth (Gwen/Gwyn)
Morwenna (Wenna, Wen, Mor, Mora)
Ivanna/Evanna (Eva/Iva, Anna)
Soleil (Sol)
Pipaluk (Pippa, Luk)
Elskede (Elska)
Elysia (Elli, Sia)
Sylvana (Syl, Vana, Anna)
Lilja/Lilia/Liliya/Lilya (Lil, Lily)
Liliwen (Lili)
Wisteria (Ria, Wish)
Boy:
Llewelyn (Lew, Welly, Wel)
Adalbert (Adal, Bert, Albie)
Alaric (Ric, Lar, Alar)
Amalric (Ric, Amal, Mal)
Everard (Ever, Rard, Rar, Ver)
Leopold (Leo, Pol)
Odovacar (Dov, Oddo (like Otto), Car)
Beowulf (Beo, Wolf, Be)
Galahad (Gal, Had, Lad)
Sylvester (Silver, Sill Silv, Ves, Vester)
Tobias (Tob, Toby, Bias)
Waldemar (Wal, Wald, Waldo, Mar, Dem, Ald)
Christoffel (Toff, Cris, Rist, Fel)
Marinus (Rine, Rinus, Mar)
Olivier (Oll, Ollie)
Akseli (Axe, Sel)
Kalevi (Kale, Levi, Lev)
Lieven/Levin/Leven (Lev, Lieve, Vin)
Olavi (Olaf/Olav)
Pietari (Tar, Piet, Pete)
Killian (Kili, Lian)
Oisín (Osh)
Seamus (Shae/Shay)
Alastair/Alastar/Fifty other variants (Al, Ster)
Darius (Dar, Rius)
Valerian (Rian, Vale, Lerian, Leri)
Peregrine (Pip, Pippin, Grin)