It's funny, Costa is so great beating his man, but on right he cuts in and that doesnt suit him (better creator then shooter), he never goes wide there to cross or pass in (leads to over dribbling when cutting in). But in left wing he goes wide and makes brilliant crosses or low passes into the box all the time. Nonstop chance creation.
The reason we arent playing him there is Ronaldo, but this game, so far, Ronaldo haven't spent a single minute on left wing lol, he has been CF throughout with Higauin as LW.