And be careful and do it at your own risk. Since I have P9 and not your device I can't test and give you guarantee..Hi, I had read those Threads - the German Forum used my older 2.81 version (which is patched with phh files cause of missing loop support for this Firmwares)
They didn't check that I made same with 2.82 (last final version) - and I think if 2.81 worked, this Version of SuperSU should be good:
https://www.androidfilehost.com/?fid=817550096634776377
TWRP you must look how it does. If possible back up your boot.img before flashing SuperSU.
SuperSU should work.
Only problem is, at the moment a new SuperSU comes released - you can't update it with official SuperSU. Then you must stay on 2.82 because I am not sure if it will be possible to update this EMUI Version to next release...
Maybe you search on xda for further information how to use this TWRP and what it can or not can...