Eun sits next to 3 phonetic neighbors — Un, Eon, and Yoon are the closest matches by sound. Most share Eun's Korean-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"silver"
"of the earth, earthling"
"Auspicious; benevolent"
"free one, from France"
"uncertain — possibly indigenous Mexican origin"
"God is gracious"
"a plain, fertile land"
"Lily; rose; from Hebrew Shoshana"
"combination of dear + beautiful valley"
"anointed one"
"God is gracious"
"harvester, reaper"
"joy; gladness"
Similar sound: These names share phonetic patterns with Eun — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Korean origins, giving them the same cultural heritage as Eun.
Rhythm: Eun is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.