Is it possible to overwrite the system factory reset option with my own backup? Please i need to know if it is possible to overwrite the system factory reset option with our own backup file. Basically, i am interested to tune the factory reset option with my own custom full system backup. 

In other words, i want to restore my custom backup when i click on the factory reset option instead of restoring the original settings of the factory.

Note 1: I have already rooted my Android device (Huawei Honor 7 - PLK-L01).

Note 2: My objective is not restoring a backup. I know how to restore a full backup. I need though to understand if it is possible to configure the factory reset option with my own backup. I really like to understand the procedure to do that if it is possible.

Thanks in advance for your help!
When you start the factory reset in the settings it just runs recovery which the actual resetting is done by. Normally, recovery just wipes everything in /data and /cache in all (and /sdcard in most of) phones, since that is all a non-root user can modify.

So a factory reset is not a fresh install of the ROM. It is just the wiping process of every made-by-user change on the phone.

I want to stress it since as much as I understand you think factory reset does some sort of overwriting. It doesn't do that. Vice versa it wipes stuff. It, by default, doesn't restore, install, overwrite anything.