What we’ll need to do is add Razer to the allowed developers for kernel extensions — we’ll basically add the Razer ID (R2H967U8J8) to the list of allowed kernel extension developers.

1. Boot into recovery mode (Restart your mac and hold ⌘+ R during startup. (Command + R)
2. Go to Utility → Terminal
3. Type “/usr/sbin/spctl kext-consent add R2H967U8J8” and press Enter
4. Type “/usr/sbin/spctl kext-consent list” and press Enter
5. When executing the command, you’ll see a list of Allowed Team Identifiers in the terminal. Make sure the Razer ID (R2H967U8J8) is inside this list. Afterwards, just reboot your machine (you can execute ‘reboot’ in the terminal).
6. Type “csrutil disable” and press Enter

Restart Mac and open termial:
1. Enter “sudo kextload /Library/Extensions/RazerHid.kext” and press Enter

Inside System Preferences → Security & Privacy, you will need to unlock the settings by clicking on the lock icon in the bottom left. Enter your user credentials and you’re ready to approve the kernel extension. There should be a note at the bottom where you can click “Open Anyway”.

You might need to reboot again. Afterwards, just launch Razer Synapse, connect your device. It should now be detected and everything should be working!

The last thing is that you have to go to recovery mode and enable csrutil by “csrutil disable”