I had this same problem on a 1998 Japanese Ford Mondeo. I only owned it for 2 months before I sold it, so I didn't really look into the problem, but my suspicion was that the transmission fluid was old and dirty, making it more viscous than it should be. This kept the torque converter from turning freely when the wheels were stopped. And sometimes if I came to a stop suddenly, the engine would stall because the stopping wheels would be too coupled to the engine via the transmission and torque converter, as if I was driving a manual and tried to stop without stepping on the clutch. It was the worst on cold mornings, but it would quit doing this once it got hot enough to reduce the viscosity to somewhere in the normal range.
Later I described the problem to someone and they told me it was probably the idle air control valve, though my explanation was also possible. Since you already checked the IAC, check if your transmission fluid is still good.