Their thoughts about red team?
ooohhh so I've actually rambled about this before to someone on discord a little bit but i never got to make a post about it so I'm glad you asked!
BLU Team - Thoughts on their counterparts:
Scout: Scout is jealous. Incredibly jealous of RED Scout. Knowing that he's a clone, and that RED Scout will get to go home and see his family again, or talk to them on the phone and send them letters makes him so mad. Scout has such fond memories of his ma and brothers. But at the end of the day, Scout isn't Jeremy. RED Scout is. It's not fair. Everytime he sees that guy on the field he wants to cave his head in with his bat.
Soldier: An almost friendly rivalry! Soldier respects the RED Soldier for his combat and bravery. They regularly blow each other up and there are no hard feelings about it! War is war! In fact it's a little fun to have an enemy that's just like you. Soldier feels weird about being a clone, but he feels no animosity towards his counterpart for it.
Pyro: You're just like me, and I'm just like you. Pyro feels a strange connection with their counterpart. Knowing that they both share the same face, the same burn scars, it's strange. Nobody else knows what they look like but them. They're fascinated by the other, but they're enemies. They're not supposed to talk to each other.
Demo: Demo feels... bad for his counterpart. Almost a sense of pity. He understands what it's like to feel that guilt about his past, the crushing weight of family expectations. It's what led him to drink as much as he does. Demo feels a sense of freedom in knowing now that he's a clone but his counterpart? He doesn't get that freedom.
Heavy: Heavy is angry and bitter. What gives RED Heavy more right to be the real Mikhail than him? He remembers- to him, he was there. He fled with his family out of the hands of their oppressors back in Russia... At least... It feels like he did. Heavy just wants to see his family again, to know they're alright. But they aren't his. They aren't supposed to be.
Engineer: Engineer can't help but think the RED Engineer must be some sick son of a bitch. Spy had told him about how the RED Engineer sat by and helped the RED Medic with his experiments. He wouldn't trust him even if his life depended on it. His counterpart is loud, reckless, rude even. Engineer thinks he's more deserving of the name Dell Conagher than his counterpart ever was. Engineer tells himself he could never do something like that to someone like the RED team did to Spy. Not even to an enemy. Right?
Medic: She's fascinated by his work, but he disgusts her. She could NEVER let herself be like the RED Medic. Medic always finds herself in his shadow, unable to keep up with his accomplishments. The medigun, the übercharge... They're all things that are just an imitation of her counterpart's creations.
Is she unable to keep up with him because of her inability to do the things he does? Is she weaker, or does she just have a heart? Seeing the effects of the experiments done on Spy, she could never let herself hurt someone like that for her own gain. She still has that burning need for knowledge, to experiment. At least Medic has one always willing test subject to use, herself.
Sniper: Sniper doesn't know him at all. The RED Sniper is foreign to him. Sniper knows his name, Mick Mundy. He's from Australia. He wears a hat and sunglasses just like him, he lives in a van just like him, he even knows how to shoot and kill with a rifle. The rest? He's not sure. Sniper doesn't remember the rest. Mick might look like him, but Sniper isn't Mick. Sniper doesn't remember being Mick.
Sometimes Sniper stands at a broken payphone outside the base, knowing it holds some significance to him. But he doesn't even know who to call. Eventually, he might remember. Maybe if he holds the phone to his ear he might hear something. Maybe someday he could ask Mick himself. But he can't bring himself to. Not now.
Spy: Spy hates his counterpart. The RED Spy made these mistakes, these choices that haunt him. Couldn't he have found a way to not abandon his son? To not abandon the woman he loved? Spy might not have any desire to see Scout's mother again, but it haunts him. He hates the bitter, cruel man his counterpart has become over the years. Spy has seen the way RED Spy taunts the others on the battlefield after killing them, sometimes laughing at Spy's own teammates. Spy kills because he has to, but he thinks RED Spy must kill because he enjoys it.