I have first Mac where I successfully sign and notarize my apps for macOS outside AppStore.
On second Mac I downloaded existing "Developer ID Installer" and "Developer ID Application" certificates and installed in KeyChain. Also I downloaded and installed Intermediate Certificate.
When I try to sign anything on second Mac I see the error:
"error: The specified item could not be found in the keychain."
Also I have a file "CertificateSigningRequest.certSigningRequest" saved from first Mac. No idea how to use it.
What I missed in this nightmare to get it work? And keep codesigning on first Mac, too.