Mitsu sits next to 4 phonetic neighbors — Mitsuko, Kiku, and Yuki are the closest matches by sound. Most share Mitsu's Japanese cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"honey; nectar"
"eagle nobility"
"bee"
"joyful spirit"
"grace"
"ornament, adornment"
"bold in counsel"
"yew tree"
"Thunder; feminine form of Thor"
"divine love"
"beloved, wished-for child"
"song of joy"
"modern invented name, possibly related to traveler"
"beginning, origin, creation"
"creative American elaboration of Rhonda"
"black drink crier, one who shouts at the sacred ceremony"
Similar sound: These names share phonetic patterns with Mitsu — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Japanese origins, giving them the same cultural heritage as Mitsu.
Rhythm: Mitsu is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.