Mathieu sits next to 3 phonetic neighbors — Matthew, Matteo, and Matias are the closest matches by sound. Most share Mathieu's French-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"gift of God, gift of Yahweh"
"light, illumination"
"rain"
"royal, kingly"
"spring-like, of the spring"
"of Julius, belonging to the Julian family"
"associated with the master of color"
"greatest, surpassing all others"
"from the ash tree valley"
"man, manly"
"estate of the fifth son"
"hawk"
"from Rome, Roman citizen"
"guest, stranger"
"sky, heaven"
"lord of the estate, powerful at home"
Similar sound: These names share phonetic patterns with Mathieu — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew origins, giving them the same cultural heritage as Mathieu.
Rhythm: Mathieu is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.