Dishonored 2 has unfortunately launched with a range of issues affecting many but not all PC users. The worst issues appear to be random crashes and a frame rate that fluctuates widely, as we found in our own analysis of the game. Since then, Arkane Studios has been working on a patch and while we don’t have the final version yet, you can get your hands on a beta version through Steam if you want to start playing.The Dishonored 2 beta patch can be accessed through Steam, simply right-click on the game in Steam, go to properties, go to the beta tab and opt-in. If you are a Nvidia user, you will want to grab the latest hotfix driver (375.95), which you can find, HERE. There is no specific driver update yet for AMD users. However, if you are a CrossFire user, you are advised to revert back to the 16.10.2 driver.
Source: Dishonored 2 gets PC beta patch, ‘begins the process’ of fixing | KitGuru