Step 7 – Once your phone is in Bootloader Mode, type in the following command and press Enter.
fastboot flash recovery twrp-3.1.0-0-vienna.img
That’s it! the TWRP recovery is now installed on your Huawei P9 Plus. You can enter Recovery Mode (TWRP recovery) by pressing and holding the Volume Down + Power keys together.
You may also like to check out our Huawei P9 Plus section for official firmware updates, custom ROMs, tips and other tutorials.