Hi Francisco,
You can add node modules to a nodejs-project. Information on how to do it can be found in each plugin's README.md:
https://github.com/janeasystems/nodejs-mobile-cordova#node-modules
https://github.com/janeasystems/nodejs-mobile-react-native#node-modules
Information on how to do it for the native library can be found on these sample projects:
https://github.com/janeasystems/nodejs-mobile-samples/tree/master/android/native-gradle-node-folder
https://github.com/janeasystems/nodejs-mobile-samples/tree/master/ios/native-xcode-node-folder
I hope this was helpful.