I don't see a reason why he cant do this from the left though. If you look at the most sucessfull teams over the last 5 or 6 years (Barca/Madrid/Liverpool/City to a certain extent), their primary goal scorers have played out wide.
I'd argue that they actually have more space to score goals, as they don't have to play with their back to goal as much against two CB's, and can make those out to in runs between fullbacks and Cbs.
I'm obviously not comparing their quality, but I see Auba's style on the left as similar to Ronaldo in the latter stages of his career, where he plays on the left, but main objective is to get into the box and score the goals. Having another center forward in the box occupies the CBs, which makes this easier for him IMO.
I do agree that creativity is an issue, but if we do move towards a 433, then I'd hope that would come from the two number 8s.
He's proved he can do a very good job from the left, no doubt, and against the right teams, ala Chelsea where they left copious amounts of space he can crucify them, but he also offers far less when teams sit deep as unlike a Ronaldo he is less creative, not a criticism, its just not his game, probably why we got Willian, so we can mix it up, at the moment if Auba isnt wide left we are relying on emerging talent to be consistent i.e Saka/Martinelli, i'd just rather see my main goal threat through the middle with something more creative behind and to the lw dept.
I'm not disputing the guy is elite, i just prefer my wingers as wingers and strikers as strikers....