UXP hybrid plugin for macOS: “Failed to load Addon” — signing/notarization issue?

I developed a UXP hybrid plugin for Photoshop on Windows and prepared a macOS version. I adapted the file paths for macOS, then used GitHub Actions on a macOS runner to build the native addons for Apple Silicon and Intel. I packaged the result as a .ccx file.

On a Mac, Creative Cloud appears to install the plugin, but macOS shows this warning for stroke-recorder-native.uxpaddon: “Apple could not verify … is free of malware.” Photoshop then displays “Failed to load Addon.”

The .uxpaddon binaries are not signed or notarized with an Apple Developer ID certificate. Could that be the cause? Do I need to sign and notarize both binaries before packaging the .ccx, or are there other configuration or packaging steps I should check? Thanks