According to a new report, the Xiaomi 12 will launch next month with a 50 MP primary camera that also has approximately a 1/1.3-inch optical format. If correct, then it would rule out the Xiaomi 12 from inheriting the ISOCELL GN2 that Xiaomi uses in the Mi 11 Pro and the Mi 11 Ultra.
https://www.notebookcheck.net/Xiaomi-12-tipped-to-launch-with-a-Samsung-ISOCELL-GN1-or-a-Sony-IMX700-50-MP-camera.578888.0.html