Joni sits next to 4 phonetic neighbors — Jonah, Joni, and Johnny are the closest matches by sound. Most share Joni's Scandinavian cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"God is gracious"
"God will uplift"
"magic, spell, enchantment"
"ancestor's descendant (alternative etymology)"
"God enlightens, he shines"
"God gave"
"invented name, no inherent meaning"
"deep valley dweller"
"new house, new home"
"Yahweh is gracious"
"from the fortress"
"carrier of burdens"
"tall, noble"
"illumination, radiance"
"lord, ruler"
"yew tree"
"born on Sunday (in some traditions)"
"fingernail, claw"
"weaver"
"a days travel; a trip"
"natural, undomesticated"
Similar sound: These names share phonetic patterns with Joni — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew via Scandinavian origins, giving them the same cultural heritage as Joni.
Rhythm: Joni is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.