Only way the Saints can afford to trade him is if the Hawks would take on his full salary other than his prorate bonus, otherwise the Saints couldn't afford to. Plus it would have to be a post june trade even then, as a pre june and they would get very little cap savings so don't see them doing it.
If the hawks did that they would be paying him
19 mil roughly this year.
19.5 mil next year
33 mil his last year which means cutting him or extending him and coverting most of that 22.4 mil base salary into bonus stretched out over several years.
Yes he is great but honestly I think that is way to much to pay for a RB.