You can migrate a vSphere environment that uses a collapsed cluster.
In a collapsed vSphere cluster, all NSX management VMs and workload VMs must be initially attached to dvPortgroups. After migration, the management VMs will be attached to the NSX VLAN segments.
The management VMs in the NSX include appliances such as NSX Manager, vCenter Server, VMware Identity Manager, and so on. The NSX VLAN segment ports to which these management VMs connect are blocked in two cases: when these management VMs are rebooted after they were migrated in-place by the Migration Coordinator, or when they are moved from NSX-V hosts to NSX hosts by vMotion in maintenance migration mode. Therefore, the management VMs might lose connectivity in such cases.
To prevent this problem, create a "management_vms" tag category, and add tags in this category. Assign a tag from this category to all the management VMs in the NSX environment. These VMs will be attached to unblocked VLAN segment ports.