What if my wallet gets hacked and the hacker transfers all BTC to his account? Is there is any way to get it back, or to open a dispute to specific address or anything else?
All BTC transfers are final. If a hacker moved your BTC elsewhere, you can't get it back.
You have to keep your funds safe. See https://en.bitcoin.it/wiki/Securing_your_wallet.
If the hacker moves your BTC to an exchange for cashing out then there is a chance to get it back (not via bitcoin protocol but via police / legal action). See for example my statement on another similar question: Bitcoin disappeared from paper wallet
This works in many cases, if the hacker isn't very carefully. Usually blockchain analysis allows to combine the 'stolen' address with other BTC addresses belonging very likely to the same owner. Then the inputs and outputs can be traced to see if one of the addresses e.g. sent BTC to a known exchange address and the exchange knows if it was cashed out there (to what bank account). Nowadays there are millions of BTC addresses known as exchange owned. And even if analysis isn't successfully today it could be tomorrow.