How can I make a Cat more comfortable living outdoors when he was raised indoors?

[Coco]

I live with friends in a house. One of my friends' cats hasn't learned to socialize or at least keep to himself in the past 4 yrs since she brought him in as around 4 mos. old. I tried a calming collar for a yr, bought multiple perches & scratching posts & beds, & there's a litter in almost ever room for the 5 cats. After several injuries to the others that seem to be catalyzed by this one, she decided he'd be better off outside. He is SUPER OVER affectionate to people in an almost obnoxious way when you see how insecure he acts around the other cats. He's tried to dominate unsuccessfully, & generally just annoys even the most peaceful sweet cat purge bunch. I am against an indoor cat being thrown outside. While I grew up with an outside cat that stayed on my childhood home's property & lived a long healthy happy life chasing birds & butterflies, she was from a shelter & lived outdoors her whole life with the exception of having a cat house we built & the garage on a stormy night. I have been posting flyers around town, calling every no kill shelter on Long Island, reaching out to my friends, family & Co workers, but my friend had had enough of the hissing & aggression in the house. I can't stand it anymore either, but my heart is heavy seeing her scared kitty come to our door like an outcast. He don't know what he did wrong...I put a box with blankets & food, even a litter box since he's used to that around the house that's hidden a bit.