Just contacted PONOS about this here: https://www.ponos.jp/contact/inquiry/
Here's what I said if you want to inform them too, just change "<your username> to your username:
ENGLISHです：
Good day,
I believe you might be interested in this. There's a scammer going by the name "Pera Games Studio" who is illegally selling your "Battle Cats" game on the Amazon Appstore: https://www.amazon.com/Pera-Games-Studio-Battle-Cats/dp/B0BRH3K7P6/
Kind regards, <your username>
JAPANESEです：
いい日だ、
この件にご興味があるかと思います。「Pera Games Studio」という名前で、あなたの「Battle Cats」ゲームをAmazon Appstoreで違法に販売している詐欺師がいます。https://www.amazon.com/Pera-Games-Studio-Battle-Cats/dp/B0BRH3K7P6/
よろしくお願いします、 <your username>