Hello there,
I know there are a lot of topics here about crashing but I wanted to share my experience aswell with a buddy of mine in hardcore.
So on my end the game completly froze and i had to Alt + F4 and restart.
It always happened when one of us died and the other one created either a new character and rejoined / reconnected. It always happened while the other rejoined / reconnected when the game froze… very unlucky especially in Hardcore since there is also no revive option for teammates yet..
Hope this might help in fixing it