Junkrat, McCree, 76 and Reaper consciously (or unconsciously) trying to impress their crush during combat and thinking that no one else has caught on (but literally everyone can tell).
Junkrat: probably yells out “Hey! (Name)! Watch this!” and explodes many, many things unnecessarily in front of them, until someone pulls him aside to have a talk about he’s 1. wasting supplies 2. putting everyone in danger for no reason and 3. not impressing anyone (It’ll probably be McCree, cuz the cowboy understands.) In the end, he’ll probably drag them to see some crazy display he set up that’ll like, explode a trail of gasoline into a flaming “DATE ME” sign under the guise of pulling them away from a mine he’s planted.
McCree: isn’t as reckless as he is easily distracted, and will go out of hi way to get flashy kills in front of them. It bothers everyone how he’ll say some snappy old Western movie line after every shot, which he says is part of his ‘American charm.’ When he really gets out of hand, he’ll recede into his usual flirting style (which is summed up in the ‘Hey….you come here often?’ cliche.)
Soldier76: He’s probably the most subtle with it out of all of them, though that’s no saying much. He’ll end up frustrated every time they don’t notice when he makes a good shot or something, but will just take that anger out on the mission. That’s what everyone will notice- that he’s more aggressive than usual. When someone pulls him over and asks him to calm down, then he’ll admit what he’s doing and beat himself up over it a little bit over being such an idiot. At heart, he’s a nervous little teenager whose just more used to being chased than being the chaser.
Reaper: Oh man. He tries so hard to impress everyone, all the time. It’s hard to tell who he’s aiming to impress at any given moment, but if his crush or s/o is on the battlefield, he changes the game. Instead of trying to impress them with extra flashy maneuvers or making it seem like flashy maneuvers are just his norm, he’ll try to downplay all his kills so that each one isn’t a big deal, but he rakes in a lot of bodies. Everyone will notice that he’s trying harder than usual but without bragging or making some awful Grim Reaper jokes about it, the silence will be disturbing. It’s honestly just as try-hard if not more try-hard than his usual edgy ways, but all he wants to do is seem like the effortless
cool guy murderer in front of his crush in the hopes that they find it endearing.