Sianni sits next to 5 phonetic neighbors — Sienna, Siani, and Shani are the closest matches by sound. Most share Sianni's Welsh cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"God is gracious"
"great queen"
"feminine elaboration of George"
"feminine form of Evan/John"
"home strength"
"land of the Welsh, Wales"
"messenger of Hermes, earthly one"
"happiness, fortune"
"pure, clear"
"superior, more desirable"
"traveler through the forest"
"from the Caecilius family"
"truthfulness, sincerity"
"isle of apples"
"alive, living, lively"
Similar sound: These names share phonetic patterns with Sianni — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew Yochanan via Welsh Siân origins, giving them the same cultural heritage as Sianni.
Rhythm: Sianni is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.