EMUI 12 breathes new life into the Y9 Prime 2019 with several design and functional overhauls:
The firmware update introduces several "neuromorphic" design elements and functional improvements aimed at smoother performance: firmware huawei y9 prime 2019 stk-lx3 emui 12
Between 300MB (for beta users) to several GBs (for those jumping from EMUI 10). EMUI 12 breathes new life into the Y9