Skin hacks? They're already existing, they are just detected though. It's almost impossible to hack in CS:GO without getting banned.
VAC, isn't the problem. Overwatch is the problem, if you're just playing TDM, CASUAL, and OFFICIAL servers, then you're probably able to wallhack or triggerbot, without getting VACCED. You are not able to play competetive with hacks, without getting banned. Using other hacks for other games, also results in a ban, for CS:GO.
I hacked i APB and got banned for CS:GO. Be carefull out there :-)