Arwen sits next to 4 phonetic neighbors — Arwyn, Arden, and Arvine are the closest matches by sound. Most share Arwen's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"noble maiden, royal woman"
"canal, channel, pipe"
"descendant of Dubh Slainghe (dark one of the Slaney)"
"rose lake, rose by the water"
"boundless, unlimited"
"bringer of joy"
"precious gem"
"God has favored me, gracious one"
"sun (via Persian Kira)"
"phonetic initials KC"
"star"
"grace, favor"
"bitter sea, wished-for child"
"lake (suffix -lyn from Welsh)"
"land of the Scots + lake"
"great queen, divine queen"
"consecrated, holy"
"fair, righteous"
"God is gracious"
"bearer of Christ (from Christopher)"
"faithfulness, devotion, allegiance"
Similar sound: These names share phonetic patterns with Arwen — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Sindarin Elvish (Tolkien) origins, giving them the same cultural heritage as Arwen.
Rhythm: Arwen is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.