This issue happens for all macOS 10.x. For Chinese input methods like Sucheng, it has a feature that can "Adjust word frequency" according to the frequency of usage of each word.
When I disabled the "Adjust word frequency", the word order remains the same, but no longer changes according to the frequency of usage.
How can I reset the word usage count to zero? I tried to remove and re-add the input method, the word frequency remains the same.