It is being reported that discussions have taken place between City and Hearts about a loan for the player, who moved to the Etihad this summer.
The Japanese prospect was snapped up from Gamba Osaka with the deal being completed just four days ago. City are immediately looking for a loan destination to help his development.
Hearts have endured a rough start to their campaign having won just two of their six fixtures inside 90 minutes thus far.
However, manager Craig Levein has continued to strengthen the squad with Joel Pereira arriving on loan from Manchester United on Tuesday afternoon.
The Tynecastle side could also complete a deal for veteran Glenn Whelan by the end of the week.