Lessie sits next to 4 phonetic neighbors — Lassie, Jesse, and Bessie are the closest matches by sound. Most share Lessie's Scottish cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"meadow of the holly tree"
"all, completely"
"western land, western meadow"
"wanderer"
"river crossing dweller"
"honey, sweet"
"golden, gilded"
"free man"
"thatcher, roofer"
"flowering, flourishing"
Similar sound: These names share phonetic patterns with Lessie — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Scottish Gaelic origins, giving them the same cultural heritage as Lessie.
Rhythm: Lessie is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.