Is it possible for Coinbase to reverse the transaction given that the Coinbase exchange has the private keys to my ETH wallet from which the ETH was sent? I read somewhere that if I sent it from a private software wallet to which I have the private keys and not an exchange, I would be able to do this.
~
Or is it not technically possible for Coinbase to do it and only possible for YoBit to do it?
Unfortunately, there is no way you could reverse your transaction back once it's confirmed. It's just the immutability natures.
The only hope you have is only from the Yobit side because It's technically possible to get the ETH back, but sadly, Yobit has a bad reputation and probably won't help you in this case.