@d-healey Then my job here is done.

For anyone doing it it manually, here is the code.

Thanks @d-healey as always!

Codesigning Plugin
codesign --remove-signature "MacHD/User/Desktop/PluginName.vst3"
codesign --remove-signature "MacHD/User/Desktop/PluginName.component"
codesign -s "Developer ID Application: YOURTEAMID" "MacHD/User/Desktop/PluginName.vst3" --timestamp
codesign -s "Developer ID Application: YOURTEAMID" "MacHD/User/Desktop/PluginName.component" --timestamp

Build Installer

Sign Installer
productsign --sign "Developer ID Installer: YOURTEAMID" "MacHD/User/Desktop/PluginName.pkg" "MacHD/User/Desktop/Signed/PluginName.pkg"

Notarize Installer
xcrun notarytool submit --apple-id "YOURAPPLEID" --password "App-Specific-Password" --team-id "YOURTEAMID" "MacHD/User/Desktop/Signed/PluginName.pkg"

Wait For Upload To Complete

Staple Installer
xcrun stapler staple "MacHD/User/Desktop/Signed/PluginName.pkg"

Check Status (Accepted)
spctl --assess -vvv --type install "MacHD/User/Desktop/Signed/PluginName.pkg"

FYI: Just a tip coming from the altool manual notarizing. I used to have to enter my TEAMID including my name like "My Name (GD78YHD87G)" but with the notarytool, it seems you just need the actual TEAMID Number, not the name as well.

Also, I dont think this way sends the Notarization Email Confirmation. I did a fairly small upload a while ago and have yet to receive it. I've had it take hours before, but for a much larger file. Typically it sent the email within 10 or so minutes with altool. (it does not send the email. Once the upload is complete, youre good to go).