Isabelle sits next to 4 phonetic neighbors — Isabel, Isabella, and Isobel are the closest matches by sound. Most share Isabelle's French-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"devoted to God"
"red, ruby-colored"
"pale, fair"
"star"
"work-power, industrious strength"
"woman from Magdala"
"dark beauty"
"healthy, sound"
"God will add; God increases"
"noble, of noble kind"
"night rain"
"epithet of Demeter, goddess of grain"
"noble, nobility"
"woodland clearing by a church"
"great, noble (from botanist's surname)"
"beautiful, attractive"
"most holy"
"life, living one"
"to flow down, descend"
"daughter of the sun (folk etymology)"
Similar sound: These names share phonetic patterns with Isabelle — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew origins, giving them the same cultural heritage as Isabelle.
Rhythm: Isabelle is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.