I recommend you to start learning NSX-T as it is the future of VMware software defined networking. All new features and development will appear in NSX-T now rather than NSX-v although it is still supported.
You may please check ->Become a VMware NSX Expert Today | Network and Security Virtualization . On a lighter note, your CCNA&CCNP will be a added benefit while learning NSX. Good Luck with your journey