A well-known industry insider has offered his view on the name of Xiaomi's upcoming foldable smartphone. Apparently, the device will herald the Mi Mix series' return, which Xiaomi has left dormant since the Mi Mix Alpha.
https://www.notebookcheck.net/Industry-insider-reveals-details-about-the-Mi-Mix-4-Pro-Max-Xiaomi-s-first-foldable-smartphone.525795.0.html