Good football player, bad fit here IMO.
Achane's game is actually a lot like Tony Pollard... both straight-linish home run hitters who run tougher than they get credit for. The difference is that TP is 20 pounds heavier than him. So Pollard is a very credible inside runner in the pros. Achane is willing to run inside, but at a buck eighty-eight, it's always going to be an uphill battle for him.
Ideally, we'd like an inside runner to complement Pollard and take some hits off him in those more physical situations. And at his size, Achane isn't taking a lot of hits off anybody.
There's sort of a fun logic to backing up Pollard with another small Pollard and just permanently having that big play threat on the field. But if we hit 3rd and 2, and Pollard's not out there, then we're pretty much screwed.
IMO, Achane needs to go to a wide-zone team rushing team like the Rams or Niners. Just a place where he can float outside, put his foot in the ground, then explode upfield. And those McVay, Shanahan style teams always run the type of committee he'll need.