Mccoy sits next to 4 phonetic neighbors — McCoy, McKoy, and Troy are the closest matches by sound. Most share Mccoy's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"son of Aodh (fire)"
"divine reward (alternate interpretation)"
"forest keeper, forester"
"olive tree"
"from the marshy plain"
"candle maker or seller"
"the bear"
"little cloak, beloved"
"scholar"
"noble friend, elf friend"
"three, the third"
"watchful, vigilant (via Casey)"
"leek farm village"
"crowned with laurels, victorious"
"fire (Irish equivalent Aodh)"
"meadow, woodland clearing"
"strength, permanence"
"short form of Benjamin: son of the right hand"
"may God give increase"
"ancient, enduring"
Similar sound: These names share phonetic patterns with Mccoy — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Irish Gaelic origins, giving them the same cultural heritage as Mccoy.
Rhythm: Mccoy is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.