Harmoni sits next to 3 phonetic neighbors — Harmony, Hermione, and Armony are the closest matches by sound. Most share Harmoni's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"agreement, concord, fitting together"
"cushion, pillow"
"peace (related to Ériu)"
"eternally beloved"
"pledged to God, my God is an oath"
"beautiful, pretty"
"pure, holy, chaste"
"son of Ellis, descendant of Elias"
"noble, of noble kind"
"heavenly, sky (Polynesian element lani)"
"beautiful friend"
"ash tree pool"
"life"
"deep blue-purple color, from India"
"little Alice, noble truth"
"descendant of Séaghdha"
"heavenly ocean, royal sea"
"the desired one"
"year of release, liberation"
"variant of Jackie or Casey"
"hare's meadow, hare's clearing"
Similar sound: These names share phonetic patterns with Harmoni — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Harmoni.
Rhythm: Harmoni is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.