Tl:dr, git gud, Mozambique sucks almost as much as your attitude towards a counter argument.
First of all, the worst type of gamers are ones that rely too much on the meta, and no, wraith is one of my least played characters and despite what you may think i rarely use the wingman and peacekeeper, don't be so quick to judge me and my gameplay style just because you have a major issue with some parts of a game, if these weapons were really a problem then they would have been nerfed within the first week.
Listen, those two weapons are sure heavy hitters but they still have disadvantages, especially in long, drawn out battles.
Just taking a look at a basic dps chart you can see that other guns can out damage them easily, it's all situational.
You'll always lose and complain and cry that it's not your fault because "that gun is op" when really that player is just good enough to put himself in a position or situation where that gun excells compared to another gun.
Characters have counters in this game, and so do the guns.
To counter the wingman, get close, the closer the better, its hard to aim at someone when they're in your face and jumping around you with the wingman, but not with other guns like the R99, Alternator, Prowler, And Eva-8.
To counter the peacekeeper you get higher or lower than them, doesn't matter as long as you're not running directly at them like a monkey.
"Don't do it i have the high ground" is a thing that exists.
For the Peacekeeper that also exists with the low ground.
Literally all you have to do is learn how the game works, the players work, and the guns.
You can even go so detailed that you can tell what level barrel stablizer they have based on their recoil, or shotgun barrel they have based on how fast they are shooting, the simplest example is thinking "oh * he has a level 3 extended mag" when someone never runs out of a clip when shooting at you.
I'm not some random toxic player that uses the most op weapons and denies they are op just to feel superior or better than everyone else, above all else i have fun with the game and help everyone else have fun.
I'm just some random pro player that knows his *, and the * that i know is that all weapons except the Mozabique are both overpowered and underpowered.
It all depends on how you play, how you position yourself, and how much you know about the game.
All you need to know to win any game and against any gun is their effective range.
Play the game more and you'll understand it, but don't play only to understand it, don't forget to have fun, and loosen up, if you wanna cry about a gun then cry about how useless the Mozambique is like every other pro.
