Xiaomi Mi A2 is a lot better phone than Huawei Nova 3i and that too at a much affordable price. Both of them almost similar specifications apart from that Xiaomi Mi A2 supports Quick charging but lacks expandable memory option.
Huawei Nova 3i has some uniquely advanced features that make it win the battle against Huawei P20 Lite and Asus Zenfone 5. Huawei Nova 3i firstly have a dual primary (16+2 MP) as well as dual front (24+2 MP) cameras which is really good for portrait shots. Secondly, it has more battery capacity and the best HiSilicon Kirin 710 processor.
Xiaomi Redmi Note 5 Pro is a good option under then budget of 15k,It is equipped with a wide range of strong features.It has massive storage,has lag free performance.The cameras are excellent and assist in capturing excellent images.Xiaomi Redmi Note 5 Pro