No, the Xiaomi Mi A2 does not support 5G. In India, the Xiaomi Mi A2 was released on January 23, 2020, and the 5G network will be available in 2022. As a result, the Xiaomi Mi A2 does not support the 5G network.
Xiaomi Mi A2 5G
Xiaomi Mi A2 is supportable up to a 4G network. Globally 4G supported brands of this phone are 1, 2, 3, 4, 5, 7, 8, 20, 38, and 40.