Japan probably released its first anime related ones in 2003 as in the astro boy proof coin set, but that was only in the medal, like in the hello kitty proof set, but nothing before 2002. Most probably Japan got the idea of using animes on coins ever since then... (hehehehe)
http://www.mint.go.jp/eng/coin/link/e004.htmlHonestly, I just thought it was funny that some small island designed some random coins and it just had to be the most "popular" one, which happened to be Pokemon. *lol*