The MG42 is far from being op, it’s simply the standard HMG that all others are taken from (At least in theory).
MG42: all around very good.
MG34: weaker in every way to compensate for OKW having better infantry.
M2HB .50 cal: more expensive HMG that can damage light vehicles while still being very powerful vs infantry. Only major downside compared to an MG42 is that it’s more expensive.
Vickers HMG: better damage, worse suppression, no anti vehicle ability but can shoot farther when in a garrison. Trades utility against light vehicles for better area denial when combined with a garrison or trench when compared to the MG42.
1910 Maxim HMG: faster set up time and with a more durable 6 man team, the Maxim is meant to trade firepower for mobility and survivability to allow it to be used more aggressively. (Death loop bug kinda destroys this, but that’s not by design. Hence the current Maxim is considered by many to be up and has been changed a lot in an attempt to normalize it.)
1938 DShK HMG: the only doctrinal only HMG is similar to the USF M2HB in its role as an HMG that can also threaten light vehicles, but is locked to only a handful of Soviet doctrines. (Honestly I couldn’t tell you which one is better on paper, but they are pretty comparable in their intended roles.)
Back on topic, the Cromwell does suck though. I’d like to see it’s MGs get a damage boost so it can be more like a T-34/76 in its utility, but without ram and a bit better vs medium tanks.
When you're playing EZ mode v1 you have the MG42 is a starting unit despite the fact it can pin 4 sqauds at once, despite the fact it's only 260 MP, despite the fact it is available in addition to a sniper and mortar with in the first minute of the game. It is OP as hell. The only faction that can deal with it reasonably well is Soviets because of the Scout Car everyone wants to nerf all the time.
EZ mode V2 doesn't have an MG42 but the MG34 is basically the samething just slightly worse on suppression. Basically the way EZ mode v2 is setup where the MG isn't available until t2 is how the MG42 should be.