Not sure how many people thought about this but all of Tails’s counterparts were bullied for different reasons. All of their names are connected to said bullying.
Nine was bullied due to his appearance. The older Foxes thought it was funny that he was born with with 2 tails instead of one. (I suspect that Tails’s old bullies counterparts might’ve ended up in the same location, similar to Eggman’s counterparts.)
As a result, Nine became insecure about his real tails and made several mechanical ones to use against those bullies or creeps, as he calls them. Nine’s mechanical tails, quickly became his namesake and he decided that he wasn’t going to like or care about anyone unless they worked hard to prove they deserve his affection.
Nine also might’ve made the mechanical tails with the idea of “You don’t like My real tails, which are of no danger to you? Fine! Let’s see how you like My Metal tails, which can and will destroy you if you don’t stop!”
When Sonic called him “Tails Nine”, Nine hated it since while Sonic meant it as a affectionate nickname, that doesn’t change the fact that Nine spent at least half of his life with “Tails” being used as a derogatory nickname.
Sails meanwhile was bullied due to his occupation. Because of how Dread treated Captain Jack and the rest of his old crew, they grew resentful and began targeting Dread, Batten, Black and Sails.
As a result, Sails became somewhat paranoid as he quickly accused Sonic of being a member of the old crew and wanted to attack him until he realized that Sonic was too fast to be a member of the old crew. Similar to the rest of the crew, Sails doesn’t have much fighting experience since Dread temporarily quit piracy after Captain Jack turned against him.
I’m calling the accusation paranoia because The only vehicles around belonged to Dread, Batten, Black and Sails. Plus Sonic was unarmed and by himself. (While Sonic has superspeed, can teleport and has beaten enemies on multiple occasions, Sails had no way of knowing that.)
Sails presumably got his nickname because he specializes in working with sails. He appears to be shown napping in one and the other Counterparts of Tails got their names due to what they do.
Mangey was bullied because of his wild nature. Given what the word Mangey means, his name likely originated as an insult. Mangey is the only one of Tails’s counterparts who didn’t know how to fly until after meeting Sonic.
Mangey has a monkey see, monkey do mindset. After witnessing the other scavengers treating the plants badly, he quickly copied. So Thorn sent him to live in the canopy just like the rest of the scavengers. Every time Mangey was successful in getting food, it was quickly taken away by someone else.
Feelings is the only word that Mangey can say and Mangey was the only one who liked Sonic’s idea of everyone talking about their feelings. (Possibly because he’s used to nobody caring about his thoughts and he wanted that to change).
