... even if it's true, the man asked for help, it was not a balance discution.
In my opinion, any strategy against this combo-abusive tactic has a 50% chance to fail, but maybe you won't get unlucky.
What me and my team mate used in EARLY GAME:
Player nr 1 - A lot of grens and nothing else. If the map allows you, you will achieve some flanking with them, while M3s cannot really close in. If you cannot flank efficiently or the map doesn't allow, add a mortar. You need actively use buildings and micro your grens. If you cannot reach some buildings before he does, always engage maxims with grens from green cover - they will get supressed realy late that way. 2 gren squads in green cover concentrating fire on a maxim will make you smile. If you didn't cap an amo point, don't use amo for rifle nades. You will need it for pzfaust when the time comes.
Player nr 2 - grens, quick T2, quick SC, even 2 SCs - depends on situation. A SC in this combination can realy ruin his day if maxims are on the field because snipers + maxims need to retreat. If they don't they will be eaten eather by SC eather by grenadiers comming from behind.
Unfortunately, it's only about micro here.
Usualy in such situations guards will apear soon enough so don't be to cocky with your SC. Hopefully you managed to upgrade at list one gren squad with lmg and you will do just fine against guards. If you catch out of guard a sniper squad, follow it untill into the base if you can and kill it. A smart sov player will put mines on reteating path, so you need to be careful.
Sometimes, depending on situation, one of us or both are going mortar ht doctrines if we delt with the m3s. They are efficient agains static spam (zis spam, mortar spam, HMG spam).
Good luck.
After this is where you are facing Boss Stage N°2: ISU >
-I will just add that if you are confident, use a sniper. Constant countersniping can bleed and force the player off the map. 1 sniper is not as scary as double ones.
-Turbo mortar is also a friendly micro unit to have around. Specially on certain maps.
-Remember that everytime you force a retreat on a Guard, it´s your time to be offensive on the snipers.
@OP
Tell us their EXACT build order. It´s not the same facing a:
-T1 double sniper - M3 - ???? - Guards
-Con - T1 - M3 - Sniper - Sniper - Guards
-Con - T1 - M3 - (M3 + CE) - Sniper - Guard - (Guard + Sniper)
I generally don´t face early double sniper with M3. It´s either M3 or sniper. Double sniper can show up later nonetheless.
Against double sniper i usually gank up with my partner for either of the enemy sides. Avoid sniper or do a double pincer maneuver.
Against M3 is just a matter of patience till you get T2.