MBTI went viral on Chinese social media around 2021 and remains popular on Xiaohongshu and Douban. Most users read the four letters in English; e-rén (E人) and i-rén (I人) have entered slang for outgoing vs introverted.
The Myers-Briggs Type Indicator framework that classifies people into 16 four-letter types. Hugely trendy on Chinese social media despite weak scientific backing.