Milenia sits next to 5 phonetic neighbors — Milena, Melania, and Millenia are the closest matches by sound. Most share Milenia's Slavic cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"gracious, dear"
"place name, possibly crown or river settlement"
"rebellious"
"pure one"
"princess (via Sara)"
"dweller in the valley"
"glorious ruler, strong leader"
"miracle"
"God is gracious"
"pure, immaculate"
"whole, universal"
"river flower (Guaraní myth)"
"gift of the earth"
"of the Livius family; belonging to Livia"
"transparent, clear as crystal"
"jasmine flower"
Similar sound: These names share phonetic patterns with Milenia — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Slavic origins, giving them the same cultural heritage as Milenia.
Rhythm: Milenia is a 4-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.