You are stuck. There was time like 5 years back when Xiaomi had its dialer in all phones including call recording feature. Then due to regulations and laws it has changed. Now all global phones have Google dialer.

However you can do this – unlock bootloader, install Xiaomi.eu ROM and you have not only call recording back but also many other improvements. But also problems with Google wallet payments… Anyway you should be experienced user to be able to do this.