It's a little odd to think about. That I can't name any specific product of this nature released to the Japanese market. The popularity of systems like FC, SFC, GBA, etc, you'd think would have an impact. Numerous owners of those consoles' western equivalents have fond memories of Game Genie or similar, yet I don't recall even the scarce Famicom shape GG reaching Japan. Heck the infamous Pokemon craze had no effect I know of.
Or am I just ignorant of the facts because I can't read Japanese to browse forum discussion there?