Following are the links to the NSX Security configuration guides for different software version.
NSX-T 3.2: NSX-T 3.2 Security Configuration Guide
NSX-T 3.1: NSX-T 3.1 Security Configuration Guide
NSX-T 3.0: NSX-T 3.0 Security Configuration Guide
NSX-T 2.4 & 2.5: NSX-T 2.4 & 2.5 Security Configuration Guide
NSX-T 2.2: NSX-T Secure Configuration Guide
NSX for vSphere 6.4: NSX-v Secure Configuration Guide
NSX for vSphere 6.3:
https://communities.vmware.com/docs/DOC-28142
https://communities.vmware.com/docs/DOC-27674
--The VMware NSX PM/TPM Team