So Lemontree have revealed the mystery figure, it's a Shockwave based on the Decepticon ship from the 86 movie.
22cm tall, and they'll be returning to their movie stuff right after. This figure's bot mode will be revealed in a few days, apparently. I've got all this info from the weibo you can find here:
https://m.weibo.cn/status/4453118421288728?fbclid=IwAR1SWRR9PbMMitbWS1oLm6qPgwLO3MLKnL48E7u4fanFRxvd6xo1vTNo1GI