Assuming the current set up is accurate, I like this buy for Japan: 1 transport, 2 inf, 1 art and 1 tank
Airstrike on the British India fleet (2 fighters, to land on carrier in sz 37) as well as the US Battleship at pearl (4 fighters to land in sz 62). The Cruiser and Battleship to knock out the US fleet at Philippines. 1 inf from Carolines to Borneo with the naked transport, 2 inf from Carolines to East Indies with the destroyer to cover. 1 inf +1 inf from Okinawa/Japan, and 1 inf + 1 tank from Iwo/Japan to either Manchuria or Bury, depending on what the Russians do.
On the mainland you only really need to hit 2 Chinese spaces in the first round to screw them out of the third inf unit, so I favor Fukien and Suiyuan or Hupeh since they allow you to land the Formosa fighter in French Indo China, and the Manchuria fighter either in Kiangsu or FIC depending on how the attacks go.
Assuming reasonable luck, that should leave Japan with 2 transports (plus the new one for a total of 3) along with 2 carriers and 3-4 fighters in sz 62 (or you can land one in Manchuria if extra defense is needed), and 1 carrier and 1-2 fighters in sz 37. With no immediate threats in the next round, you have the option to expand in whichever direction seems the most advantageous (depending on what the US decides to do.) If the UK goes IC in India, it shoud be fairly easy to take by round 3 or 4, if not then you can hit the Russians instead, or continue to push across the South Pacific, provided the USA doesn’t stay and fight. Either way you’re poised to pick up 2 NO’s by the end of the second round.