Oh sits next to 5 phonetic neighbors — Bo, Mo, and Jo are the closest matches by sound. Most share Oh's Chinese/Korean (吳)-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"from the state of Wu (ancient Chinese kingdom)"
"exalted, noble, high"
"defender of men; little saint"
"nickname name (Thai given name)"
"God's victory, victory of the Lord"
"from Laurentum; crowned with laurel"
"from Florence, blooming"
"eagle warrior"
"one of the Vandal people"
"river crossing dweller"
"garden enclosure"
"sun, radiant light"
"hammer, mallet"
"free man"
"moral principles, code of conduct"
"son of Jack, God is gracious"
"Calm; composed; dignified; of great weight and gravitas"
"God"
Similar sound: These names share phonetic patterns with Oh — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Chinese/Korean (吳) origins, giving them the same cultural heritage as Oh.
Rhythm: Oh is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.