Manchester city left wing is already empty after the departure of Jack Grealish and so in Manchester City he has a higher probability of playing in the X11 sheet.
Manchester City left wing is actually full, with plenty of potential candidates there. If Pep Guardiola wants Rodrygo, he'll have to sell Savinho. Even then, I think Doku can still compete for the position. On the other hand Liverpool needs a left winger far more than Manchester City.