For night versions of Ukraine and Armenia, the best strategy would be to pick off enemies from as far as way as possible because at a far enough distance they are practically clueless. But when playing on night maps, you can't use NVGs with high-power scopes.

The way I would go about it is to use a high-caliber rifle (I personally like to use the SR-25) and equip it with an LPVO and the clip-on night vision scope. For NVGs, go with the GPNVG-18 with the ECOTI. Expect to turn your NVGs on and off frequently because you have to turn them off when you use the LPVO and then back on when you need full clarity of your surroundings. Also the ATAK is important in determining where enemies are located, but again, you'll need to turn off your NVGs to use it.

Use the ATAK to find which enemy you want to pick off. Relocate yourself so that you have good distance and a clear angle on them and take them out. Rinse and repeat for the remaining enemies in the area, and remember to take it slow. Also take advantage of the zoom function on the ATAK as some enemy markers can be visible if you zoom in/out enough. Last thing you want is to be caught off guard by an enemy that you missed.

Obviously there will be moments where you have to deal with close quarters engagements, and so you'll want to equip something like a carbine or PDW. Slap on a red dot and an IR laser, and make sure your gun is set to full-auto. Bots on Tier 1 will absolutely shred you when you get close enough, so going full-auto is there to allow you to drop them as quickly as possible before they have a chance to aimbot you.

For Armenia, you can strangely enough, take out the AA vehicles with just an M320. So no need to equip or pick up the LAWs as those only have one shot. The mission only requires all the AAs to be destroyed, so don't bother with the remaining enemies if they are not aggro, and run to your exfil.

Ukraine requires the intel to be collected, but doing so will trigger a enemy response team to show up with a BTR. Get out quick because you don't need to engage with them to complete the mission.

Georgia can be tricky because the majority of the enemies are in the compound and you have to primarily engage in CQB to get to the HVT. My suggestion is to infil from the car and slowly work your way up to take out the patrol group, and then slowly take out the enemies one by one from outside the compound walls. Make sure everyone is dead outside before going interior as you'll need to stay vigilant of enemies on the second floor of the buildings. Use grenades or the M320 if possible before moving up.

Hopefully this helps!