At the Mobile World Congress currently underway in Barcelona, Xiaomi took to stage to unveil the upgraded Mi Mix 3. The new Mi Mix now features the flagship 7 nm Qualcomm Snapdragon 855 SoC and support for 5G connectivity via the Snapdragon X50 modem. The rest of the specifications are identical to the original version including the slider mechanism and ceramic build.
https://www.notebookcheck.net/Xiaomi-upgrades-the-Mi-Mix-3-with-a-Snapdragon-855-and-5G-connectivity-for-EUR599.410693.0.html