Dagny sits next to 4 phonetic neighbors — Maggie, Daphne, and Danny are the closest matches by sound. Most share Dagny's Scandinavian cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"new day, dawn of a new day"
"innocent, clear"
"Torch, bright one"
"ever powerful"
"echo, sound"
"lion-hearted"
"shelter, harbinger"
"victory, triumph"
"goddess"
"demigod, hero"
"the other Aenor (origin of Provençal form)"
"Variant of Anastasia, of the resurrection"
"anointed one"
"peaceful, calm"
Similar sound: These names share phonetic patterns with Dagny — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old Norse origins, giving them the same cultural heritage as Dagny.
Rhythm: Dagny is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.