Japanese Korean Army ended in 1945.
Japanese Korean Army was created in 1904.
That would be a tough call to decide which is better. Both armies are very good. The question does not specify North or South Korean, but either would compare well with the Japanese army in terms of quality.
Imperial Japanese Army ended in 1945.
Japanese First Army ended in 1945.
Japanese Fourteenth Area Army ended in 1945.
Japanese Eleventh Area Army ended in 1945.
Japanese Seventh Area Army ended in 1945.
Japanese Burma Area Army ended in 1945.
Japanese Fifth Area Army ended in 1945.
Japanese Second Area Army ended in 1945.
Japanese Fifteenth Area Army ended in 1945.
Japanese Tenth Area Army ended in 1945.