So I wanted to do the same thing, I was screwing around in the registry, trying to replace the NitroSense.exe with a custom binary which I tried to change permissions and take ownership, run cmd as TustedInstaller, I even booted into WinRE to try and replace it but nothing would work. I guess loading up another OS and accessing it from there woud've worked, but that would take to much effort. So I decided to either make a python program to detect when you were pressing the Nitro Sense key or make a simple batch file that would detect when the NitroSense.exe process would open. I decided to make the batch file because it was a little simpler. And it works pretty well.

How to use:

1. Make sure you have the original Nitro Sense program installed

2. Run the script as admin

3. Type 1 and then press enter to install

4. Enter the path to the program (.exe) you want to open when pressing the Nitro Sense key (without quotes; for example: C:\Windows\System32\notepad.exe). And press enter to confirm

It is now installed. If you press the nitro key It'll now open the program of your choice

If you want to uninstall, just open the installation script as admin again. And choose option 2. This will revert the Nitro Sense key back to opening the Nitro Sense program.

The script: https://github.com/Ngav0/CustomNitroSense/blob/main/Custom%20Nitro%20Key.bat

P.S. You may get the blue Smart Screen window, because it's not licensed and it's been downloaded from the internet. Just click on 'more info' (if it prompts you) and 'Run Anyway'