As far as I'm concerned ECUs are the Devil's work 🙂
What I find surprising is that, if the issue is present on the car the motor was in originally, from one of the world's biggest motor companies .... and rev-hang to me suggests at least some safety/driveability concern .... how come, post Nader and Pinto, FoMoCo didn't definitively sort it? And we can piggy-back on that solution?
Tho I'm the first to admit my choice of a crossflow was dictated by my desire for a car without computers so am only peripherally knowledgeable about such things.