Eutha sits next to 4 phonetic neighbors — Eudora, Edna, and Utha are the closest matches by sound. Most share Eutha's Greek-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"good; well; true"
"elf-friend, friend of elves"
"truth"
"free woman (via Charlotte)"
"good, excellent"
"Praise, offering"
"farmer, earth-worker (from George)"
"Dorian woman, from the Dorian people"
"coal black, dark-complexioned"
"modern variant of Majella"
"God is gracious"
"fortune, riches"
"king"
"little fortress, little stronghold"
Similar sound: These names share phonetic patterns with Eutha — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Eutha.
Rhythm: Eutha is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.