I like both, and I say them differently.
Emilia is "Em-MILL-ya" and
Amelia is "Uh-MEEL-ya".
Emilia gives me the impression of a young Hispanic woman who is also fluent in English and Italian. She's short and petite with blond-streaked brown hair and brown eyes.
Amelia gives me the impression of a little girl, about 2, 3, 4-ish, with curly blond hair, very energetic and playful and always keeps her parents on their toes.