Macsen sits next to 5 phonetic neighbors — Maxen, Mason, and Maxon are the closest matches by sound. Most share Macsen's Welsh cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"supreme, excellent"
"beautiful; fair"
"holy one (of Dewi/David)"
"lover of churches"
"chief, royal descendant"
"Irish Gaelic form of John"
"circular stone fortress"
"God is gracious"
"noise, tumult"
"gift of Isis"
"God is gracious"
"strong wolf, wolf valor"
"champion, noble one"
"slender, narrow"
"Winda's homestead, windy village"
"short form of Bogoris (divine gift)"
Similar sound: These names share phonetic patterns with Macsen — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Macsen.
Rhythm: Macsen is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.