If you need to provide the highest availability for the managing of your ESXi hosts while the operation changing VMK ports, you can do like something following procedure:
1. Setup a second IP address for the VCSA server from your considered subnet, like this method (multi-homed VCSA).
2. Configured a second VMKernel IP address for each ESXi hosts on that subnet.
3. Check the vCenter Server and ESXi hosts connectivity on the new subnet.
4 Remove the ESXi hosts and add them again to the virtual datacenter via the new VMKernels