Tong sits next to 4 phonetic neighbors — Tang, Long, and Kong are the closest matches by sound. Most share Tong's Chinese cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"paulownia tree, nobility (桐)"
"Famous warrior"
"the king"
"friend (invented by J.M. Barrie from 'fwendy')"
"valley peace; combination of Del (valley) and Fred (peaceful ruler)"
"reborn, born again"
"broad fortified settlement"
"market trader, merchant"
"Free man; from Germanic karl meaning man or free man, via Old Frenc..."
"spear of strength"
"ever powerful"
Similar sound: These names share phonetic patterns with Tong — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Chinese origins, giving them the same cultural heritage as Tong.
Rhythm: Tong is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.