Elena sits next to 4 phonetic neighbors — Helena, Elina, and Alena are the closest matches by sound. Most share Elena's Spanish-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"bright, shining light, torch"
"blessed ring, white circle (Welsh derivation)"
"one who rules by the spear"
"Free man; from Germanic karl meaning man or free man, via Old Frenc..."
"valley peace; combination of Del (valley) and Fred (peaceful ruler)"
"white ford, ford of joy"
"little angel"
"broad fortified settlement"
"Famous warrior"
"spear of strength"
"faithful, true, honest"
"the king"
"powerful ruler"
"hard, earnest + friend"
"paulownia tree, nobility (桐)"
Similar sound: These names share phonetic patterns with Elena — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Elena.
Rhythm: Elena is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.