I had a severe hotkey but where every time I had edited the hotkeys and tried to save them the game crashed (this only happened in the latest patch, which is the season one update).
Restarting the game or the computer did not help.
I finally managed to solve the problem by manually deleting the hotkey file on my computer and then creating a completely new hotkey profile one. After this everything worked correctly again. So it seems the hotkey file can get corrupt for some reason.