It takes two hours to travel in Japan and transfer from Korea (there is no transfer sign). If you want to check your luggage in Korea, you can check your luggage again within two hours.

It's almost impossible to check your luggage in two hours. Now foreigners need to queue up to go through customs. After more than half an hour. After getting off the plane, South Korea still needs to wait for the subway to pass the customs. Round trip for at least 40 minutes. Now there are two wharves in Incheon. There are many people on international routes. International flights end boarding one hour early. Your luggage has not been transshipped, so it is too late to transship it in two hours.