Doesn't work for me on a 3DS XL version 9.4 using a physical copy of Y. Dropped the code.bin and a pokemon.ekx (saved using the All Files option in PKHeX) into my SD root, then cleared my browser history and cookies just to be sure. Visited the website, and after a "Failed to load part of this page" message, it crashed, as predicted. Open Y up, nothing changed.