Kenji Johjima announced this past week that he was opting out of his contract with the Mariners and heading back to Japan. So far both the Tigers and Hawks have expressed interest in signing him. Here's his 2005 BBM 1st Version Best 9 insert card (#BN2):
I'm trying to think now of all the other Japanese players that went to the US, then played in NPB again. Sasaki, Yoshii, Masao Kida, Kaz Ishii, Shinjo, Hideki Irabu, Komiyama, Iguchi, and Fukumori all come to mind off the top of my head. The only Japanese players to go to MLB and retire without returning to play in Japan first that I can think are Hideo Nomo and Shigetoshi Hasegawa.