Bethesda will be releasing a free, three level demo of Dishonored 2 through Steam on 6 April. If you’ve been staying clear of the game due to PC performance concerns (reasonable – it can have pretty big problems), this is a low risk way of testing the waters.
Three levels constitutes a fairly large chunk of the game. The opening part is relatively short (and I’m assuming they’re not counting the optional tutorial bit as a level), but the next two are substantial. You’ll be able to play as either Emily or Corvo during the demo, just like the main game; and (if you opt to buy the whole thing) your progress can be picked up again in the full version of Dishonored 2.
Here’s our review from back in November 2016. The game has since been patched a few times on PC, but technical issues remain.