Xiaomi Mi A2 and Mi A2 Lite are unlikely to get native screen recorders
The Xiaomi Mi A2 and Mi A2 Lite may well still be popular smartphones, but they are coming towards the end of their lives. Xiaomi released both Android One handsets in 2018, which means that they are both into their final year of software updates. However, Google only binds OEMs to deliver security patch updates to devices for three years, no feature updates. So with Xiaomi already having released two OS upgrades to the Mi A2 and Mi A2 Lite, it means that neither device is likely to receive any features.
Hence, the Mi A2 and Mi A2 Lite will forever remain on Android 10, unless community developers bring Android 11 to the entry-level handsets. The lack of any future feature updates also means that Xiaomi will not be bringing native screen recorder functionality to either device, too. Beta versions of Android 10 had built-in screen recorders, but Google disabled the feature shortly before it made the OS public last year.
If you have been waiting for the functionality to arrive on either the Mi A2 or Mi A2 Lite, then you could always enable it via ADB commands. All you need to enable in ADB is the following command. Please note the functionality may not work entirely as intended since it is a hidden feature.
adb shell settings put global settings_screenrecord_long_press true