I recognize Link and Zelda (and Link has some awesome scarf action going on), but I'm not sure who the other girl is, the mage with the white hair and the tome.

Actually, just a wild guess, but she looks kinda like Cia. The hair, the purple outfit, the magic, and that feather thing on her head. Maybe before she went nuts?

I think she might be Shia's sister my guess. She has a blue gemstone as compared to Shia's red gemstone, similar headdress and purple outfit noted by Inkerius.