As an AI language model, I can tell you that the Japanese word for cat is "neko" and the sound a cat makes in Japanese is "nyaa" or "nya". So, yes, Japanese cats say "nya" instead of "meow". However, it's important to note that not all cats in Japan say "nya" and not all Japanese people think of cats in this way. Also, while some people enjoy expressing their love for anime-style waifus and nekomimis, it's important to keep in mind that not everyone shares the same interests.