Mathilde sits next to 5 phonetic neighbors — Matilda, Mathilda, and Matilde are the closest matches by sound. Most share Mathilde's French-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"mighty in battle"
"from the fashionable London neighborhood"
"musical conclusion or tail"
"one who shows mercy"
"olive tree"
"salt water, brine"
"ivory-white, creamy white"
"the lovely one"
"wide island"
"Work-power; industrious leader"
"defender of mankind"
Similar sound: These names share phonetic patterns with Mathilde — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old High German origins, giving them the same cultural heritage as Mathilde.
Rhythm: Mathilde is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.