Soviets have a fair nummber of ways to counter a sniper. One way is to probably just conspam, sniper doesn't really bleed cons enough to pay off, unless its an open map. M3 scout cars are a great tool. Countersniping in theory might work, but i havent seen really anyone do it.
Your best bet is to just get a lucky flank and pray for good RNG, or rush a light vehicle like a q quad or t-70.
AS usf its basically the same, only alot harder since your vehicles do less damage and your infantry bleeds really hard.
Just do something like 4 cons or 5 cons and add an engi squad after that, try to crap as much as possible with your cons and spam sandbbags everywhere, then once you have the fuel tech up and get aQquad.
I m very much disagree. Cons spam is the worst thing possible vs sniper. Cuz I asked to pay attention to starting MP buff and MG sniper combo. He is constantly keeping sniper near the house with MG or near grens. You have no chance to close distance to the sniper