Arguello was a ATG 126-130 a very good135 but at 140? he was beyond his best weights had he stayed at 135 he might have been an ATG at lightweight
I know the timelines don't quite line up and Duran never fought at 140 but I'd favor Duran over most any version of Arguello at any weight. They would be tough fights, but I think Duran has the right style, chin and skill set to beat Arguello the vast majority of the time.
Duran, the shorter but naturally heavier man, had quicker hands and feet. I believe he would have tenderized Alexis' ribs.
Duran was skilled enough to hang on the outside and was probably the best inside fighter I've ever seen. (Sorry Henry Armstrong) Duran closes the gap and wrecks him. Arguello was no slouch up close but it was definately his B game.
I always default to that Boxing Illustrated cover (?), with Duran pointing at an AA picture, and Duran sneering with his fist c0#ked.
Slightly with Curry and Bumphus, but serious with Mamby, who I always felt had the style to negate Arguello, and beat him on decision.
Arguello would have a harder time hitting Whitaker and Chavez because neither of them were as easy to hit with the counter hook like Pryor was both were brilliant defensive masters while Pyor had weaknesses in his defense. Duran never won the Jr light welter title like Whitaker did but they had the same number of fights at that weight limit and I`ve read it could of been Duran`s best fighting weight, they said he fought less reckless in those two light welter fights than he did at lightweight and his power had more effect than it did at welter, one way or another that period was Duran`s prime and he looked great at welter against Ray in their first fight and Palomino. Duran`s defense would allow him to do what he did against Leonard and allow him to pressure the way Pryor did, Roberto would of got inside using his jab and feints and slight shuffle towards Alexis and he was voted the greatest in-fighter of the last 30 years by Bert Sugar and other respected boxing experts just before Sugar died, so I think Duran might of beaten Alexis that night, shame they didn`t meet, I think by this time Roberto had moved up and fought Benitez at light middle.
Mayweather, Whitaker, and Chavez should be favored by decision. That I can only come up with 3 names in the 36 years since then speaks volumes on the esteem in which I hold Arguello's effort. I recently finished Christian Giudice's book on Arguello, using YouTube as I read to follow Arguello's career. This gave me a much better appreciation on how special he was. A deadly slugger/technician. But...he was slow. Footwork was decent, but not a strong point. Mayweather and Whitaker too defensively blessed. They're unlikely to be knocked out. Chavez has the chin to close distance and work inside. A lot of people throwing Duran around, but he was 4 years into 147 lbs by 1982. Duran in 1978/79 I assume could have made 140lbs, and I would favor him strongly over Arguello if they could have met at this weight.