I believe there is hope...!
If they have done it in 4.4.2 KitKat, i believe that there is a way to modify the apk and in the inernational version of D802. I searched for some call recording apps (rooted or not) but all work automatically, they dont have an option to enable disable whenever i want during the call...
With the korean mod i had the message "com.android.phone stopped" pop out all tha time. Thank God i had make back up files od lgphone.apk and lgphone.odex and with the help of root explorer i managed to bring my phone to the original state....i believe..!