Yep you’re still breaking the law. I run into that at side streets sometimes, I’ll have the stop but the other person thinks it’s 4 way, they wave me on, I shake my head and point to my sign and their lack of. Eventually they go, they probably think I’m a jerk, but if I go and they hit I’ll get the ticket, and when their lawsuit turns the incident into a lottery win for them I’d be stuck thinking “I knew I shouldn’t go”.
This is the basis of a lucrative insurance scam. The other car has the right of way, waves you on, crashes and you are at fault. He collects...and can claim all sorts of medical injury.