Just a short update that Watch Dogs: Legion PC multiplayer was just released without any notice with the latest update. Earlier this month they postponed the multiplayer mode for PC again reasoning that there were some errors that might crash PCs with certain GPUs.
Here is the original message:
The Watch Dogs: Legion team's message about the PC multiplayer release:
Now we can finally play Watch Dogs: Legion with friends!
Edit 23. March 2021:
Unfortunately there are still some bugs which in my case ended in crashing the Game multiple times - making it unplayble.