Sinophone markets are domains of Hasbro Asia-Pacific, not Takara TOMY.

But yeah, this packaging is clearly aimed at Hasbro's markets. I think the Chinese characters are more intended for their Sinophone markets (as it sociolinguistically feels out of place for the Japanese market). Or it could be Hasbro trying to make the packaging look more "Asian exotic" for their own Western markets. They did this before with
Hasbro Magmatron whose box has Japanese text printed throughout what is a standard Hasbro style packaging (but still is primarily English language), as well as the tag "Japanese Dinobot now available in the U.S.!"
(although it was available in non-U.S. markets like Australia too
), so part of the marketing of the toy was to remind consumers that this was originally a Japanese toy. But considering that the Kanji on this box is more sociolinguistically appropriate for Sinophone speakers over Japonophone speakers, I'd say the Hasbro Asia (principally released through Hong Kong IIRC) explanation makes the most sense.
Hasbro and TakaraTOMY can release each other's toys in their markets with consent from the other party. e.g. Hasbro Australia would have secured permission from Takara(TOMY) to release toys here like MP Ultra Magnus, MP Convoy Perfect Ed., MP Ghost Starscream, Jetwing Optimus Prime etc., and likewise any Hasbro toys released in Japan would have been done with Hasbro's permission. This doesn't include specialty import stores though (who in Australia at least, have to pay a stackload of import taxes, duties etc. which is why they're so expensive here).