Kaspen sits next to 3 phonetic neighbors — Casper, Kaspar, and Jasper are the closest matches by sound. Most share Kaspen's Scandinavian cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"treasurer"
"splendid, of radiant birth"
"Little red one"
"powerful ruler"
"bright valley"
"autumn"
"gift of God"
"Descendant of the cloud; son of Neil"
"royal warrior, brave king"
"Canopus star, bright star"
"bright north"
"son of the eternal ruler"
"generous king, he with good pastures"
"royal staff"
"deserving of praise, earned reward"
"divine bear"
"God's inspiration"
"mind, intellect, eloquence"
"brave, courageous"
"forever, always + wind/fighter (Ey + vindr etymology)"
Similar sound: These names share phonetic patterns with Kaspen — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Persian origins, giving them the same cultural heritage as Kaspen.
Rhythm: Kaspen is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.