To replace the old host with a new one while keeping NSX-T configuration intact and with minimal downtime:
Add the new host to the existing cluster.
License the new host for VMware vSphere and NSX-T.
Install and configure NSX-T on the new host like the old one.
Migrate VMs to the new host using vMotion or other methods during a maintenance window.
Test VMs on the new host for proper functionality.
Remove the old host from the cluster and NSX-T environment.
