How to force a factory reset or hard reset on Huawei devices

Huawei Nexus 6P Huawei Nexus 6P
Huawei Y6 Pro Huawei Y6 Pro
Huawei Honor 5X Huawei Honor 5X
Huawei G7 Plus Huawei G7 Plus
Huawei Mate 8 Huawei Mate 8
Huawei Enjoy 5s Huawei Enjoy 5s
Huawei MediaPad M2 10.0 Huawei MediaPad M2 10.0
Huawei Honor Holly 2 Plus Huawei Honor Holly 2 Plus
Huawei P9 Huawei P9
Huawei P9 Plus Huawei P9 Plus
Huawei P9 lite Huawei P9 lite
Huawei Y5II Huawei Y5II
Huawei Y3II Huawei Y3II
Huawei Honor 5c Huawei Honor 5c
Huawei MediaPad M2 7.0 Huawei MediaPad M2 7.0
Huawei MediaPad T1 7.0 Plus Huawei MediaPad T1 7.0 Plus
Huawei Honor 5A Huawei Honor 5A
Huawei Honor 8 Huawei Honor 8
Huawei Honor Note 8 Huawei Honor Note 8
Huawei G9 Plus Huawei G9 Plus