Elwin sits next to 5 phonetic neighbors — Alvin, Edwin, and Elwyn are the closest matches by sound. Most share Elwin's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"elf friend, friend of the elves"
"son of the wave, born of the sea"
"supplanter, held by the heel (via Jake/Jacob)"
"divine, godlike"
"God is gracious (via Shaun)"
"modern coined name with rhythmic beauty"
"lively, merry"
"western settlement"
"son of Walter, ruler of the army"
"of the elm tree, smooth stream"
"fire of God, God is my light"
"new house, new home"
"pledge, oath, measure"
"little king, kingly"
"variant of Terrell; earth puller"
"sun, throne"
"to shine, tremble with light"
"God is gracious"
"glorious gift"
"from the gray hill"
"dweller by the hedged forest"
Similar sound: These names share phonetic patterns with Elwin — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old English origins, giving them the same cultural heritage as Elwin.
Rhythm: Elwin is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.