The best way to move the Esxi hosts from Cluster to another is to Shutdown all VM's , Put the host to Maintenance mode , Disconnect the host from VC and remove the host from Inventory from old cluster and the add back the host to new cluster.
If you want to move the esxi hosts with the VM's to a different cluster without Getting the VM's down then i suggest following the below steps.
1.) Disable HA monitoring on the existing cluster
2.) Disconnect the esxi host one at a time.
3.) Remove the host from inventory
4.) Add the host to the new cluster and repeat step 2 to 4 for all remaining hosts.
Go through the below link where you can move the host as per your choice
1) Move ESXi host from cluster by placing the host in maintenance mode
2) Move ESXi host from cluster without placing into maintenance mode.