So a couple things here, first its probably a bad move to call people dumb in your suggestion. Beyond that here are some of the following issues I have with your suggestion, either with the idea or your context given:

The SVT-40 is an interesting choice for this. While its effectively Soviet M1 Garand, it also wasn't able to be widely used. Only about 1.6 million were produced, which seems like alot but comparatively, the M1 Garand had 5.9 million produced, for a much smaller army: The US army numbered around 11.2 million, with 16 million being in every branch of the military, which includes non combatants. Compare that to the USSR Red Army, which totalled up to 34 million. Out of all the guns you suggest its the only one that isn't particular famous and also rare for WWII.

Almost everything about what you said about the Thompson is incorrect. It is not a "full auto assault machine gun", I honestly don't know if anything is classified as that, it is a submachine gun. In fact it is the first every gun to be produced to label itself and be called a submachine gun. It also wasn't made in 1928, earliest form of the Thompson was made in 1918, as a gun intended for use during WWI but came too late. The popular depiction of it as a mobster gun was due to the mob using them during the 1920s. Due to it being literally the first submachine gun by the time WWII came around it was a suboptimal design, and the US would end up making the M3 Grease Gun, which interesting enough is not on this list.

Only thing I will say about the Luger is that while, yeah, Germany used them, it wasn't only germany. Its a common misconception.

The StG 44 is the only one you forgot to mention, and like the SVT-40 its interesting you pick it over other guns. While its a very well known gun and popular, it also was only produced in extremely limited numbers. Less than 500,000 were produced, an incredibly small number.

So thats almost all the issues except for the big one:

There is literally no reason to add any of these.

The SVT-40 would literally be a M1 Garand clone in game, which the M1 Garand on CCNet is pretty bad. The Luger, MG-43 and Thompson are simply not needed as we already have these types of guns in the game. The StG 44 isnt needed, and actually adding it would create balancing issues since its actually the first assault rifle ever made, we would effectively need to figure out what the class should do in terms of game balance. The only real addition you could argue for would be the M1 Carbine, since it wouldn't be a big pain balancing. But it would effectively just be a weaker M1 Garand and is that really needed?

Theres no point in Zaify wasting his time adding guns that simply won't be used.

Is the carcano used? No.
Is it in the game? Yes.
I think this is an awesome thing and will defenetly get used.

is there any reason Maxim was removed? I see you mention MG42 and I would be very happy to see some static heavy machine gun that actually makes it worth it being "glued" to one place by having some damage. But if Zaify had some reason to remove Maxim he probably isn't just gonna add MG 42. But yeah if there is no real reason, for god's sake let us glue ourselves on top of a wall and shoot like we mean bussiness

Mg42 i think was frequent in jamming and overheating easily (if i remember my history and knowledge correct) but what if it would be like an T-gehewr type gun that cannot move but has an ammo box with about 150-200 bullets but you should be careful not to get it jammed because it would have a 10-15 second cool which you cant move (maby) and wait until 1. Cannon got unjammed or 2. It cools down. This could do medium damage at close-medium range and would be useful in small trenches which are usually formed to shoot guns (like in irl) i dont know, i took the nerfing kinda harsh and lewis would just replace it by cost prb. If it has about 150-200 ammo i think it could be used in more fortified spots and more. (Remember this is all a suggestion, and i belive this post wont make it real)

So the issue with adding an MG-42 is that... it is ridiculously overpowered. It's rate of fire was so high that it was often called the "buzzsaw" with it's signature brrt. The MG-42 had a TON of issues with overheating and the usual overengineering issues found in just about every German weapon made in the second half of the Second World War. Another issue would be that the MG-42 was really inaccurate when fired for prolonged periods of time and we already have that with the Lewis Gun. As for the M1 Thompson... sure, it wouldn't be out of place in CCNet's WW1 setting, however it would cause too many balancing issues as a submachinegun. The Sturmgewehr 44 was an assault rifle and simply too advanced for CCNet's setting.

Also calling people "dum" (spelled that wrong, by the way) isn't really the best way to gain support.