The game with directx 12 is very laggy on my hardware. I followed Drummond's tutorial:

I followed the steps below to for the game to run with Direct X 11: 1 - Downloaded dxcpl from here: https://www.netvector.de/downloads/dxcpl-directx-11-emulator.exe 2 - Executed protontricks and using explorer, executed dxcpl and on it. 2.1 - Clicked in Edit List > ... > selected the game launcher > add > ok > checked on Disable Feature Level Upgrade and choose in the list called Feature level limit: 11_1. > Applied and closed 3 - Launched the game from steam.

After this the game ran a stable 60fps on medium settings.