A leaks site has posted what is claimed to be a new trademarking application filed by Huawei for a "Mate Watch". Therefore, it seems the OEM is making a new wearable specifically intended to go with the phablets of the same name. It may be joined by another accessory, the "MatePod".
https://www.notebookcheck.net/Huawei-will-start-a-new-smartwatch-line-that-matches-the-Mate-series.466429.0.html