Could you please follow up these steps to sync up these external libraries with commandline?
1: Open a remote project from studio (make sure that your SVN/ Nexus is running well at the same time)
2: Install your required external libraries by using Module view(Window-->Show View-->Talend-->Modules)
In this way, SVN/ Nexus will sync up your required external libraries automatically and then commandline will get them from .m2 repository to deploy your job.
Please take a look at my screenshots and let us know if it works.