Recording the other person, whether incoming or outgoing is a hit and miss, when it does record, it is soft. Trying to record with Bluetooth has failed all of the time and I have a mate 8 dual sim. I have registered as a beta tester and same issues.
Some phones have the bluetooth recording problem because there is a bug in the ROM of these phones, no matter what recorder in the market you are using the problem is always there.
Boldbeast Recorder can fix the problem. Please root your phone, enable the "Change Audio Control" option in the app, then you'll record calls perfectly in two directions via bluetooth. The option is visible only after you root the phone.