Trudy sits next to 5 phonetic neighbors — Rudy, Judy, and Trudie are the closest matches by sound. Most share Trudy's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"spear of strength"
"friend (invented by J.M. Barrie from 'fwendy')"
"ever powerful"
"spear rule"
"Sea of bitterness"
"noble, bright"
"renewed in spirit"
"market trader, merchant"
"Free man; from Germanic karl meaning man or free man, via Old Frenc..."
"wise counselor"
"paulownia tree, nobility (桐)"
"rock, crag, cliff"
"white ford, ford of joy"
"broad fortified settlement"
"valley peace; combination of Del (valley) and Fred (peaceful ruler)"
Similar sound: These names share phonetic patterns with Trudy — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Germanic ger + trud origins, giving them the same cultural heritage as Trudy.
Rhythm: Trudy is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.