[Fevves]

Read carefully.

If you have custom rom that enabled this hack already, you simply use x-plore or any other 3rd party file manager with capabilities to see system drives and through that file manager you should navigate to c:\private\10202be9 folder and move 101f8731.txt to some other location. Eventually delete c:\private\10202be9\persists\101f8731.cre and after that you should delete cache in your in-built browser. Restart your phone and it should be seen as i8910.
In case this modification is already coded on Z drive (only if custom rom is coded that way!), then you should have the original 101f8731.txt and put it in c\private\10202be9 folder to actually regain original i8910 phone agent.

Below is attached mine untouched file from Z drive.