I know most games using MDH %100 for default aim sens but I dont know what games using this option. How can I learn what MDH% used by Crysis, metro etc.?

not possible if games havent ads settings

Most games don't use 100% MDH. There's loads of different setups, a lot are scaled really strange and some use fixed multipliers that aren't scaled at all.

You can attempt to figure it out by learning some simple Lua turn scripts if you use Logitech or use Kovaak's sensitivity matcher. Measure the turn-rate (360/cm) for hipfire, then use that to figure out the FOVs, and then measure the turn-rates both when hipfire compared to ADS and do some math using the FOV difference and turn-rate difference.

If you can't actually adjust the ADS sens though, then there's not a lot of point in knowing how it scales.