As long as you keep the management's hostname the same, you should be able to move with just 'migrate export' on the old one (remember to use the new migrate tools!), 'migrate import' on the primary VM, change the IP in the object, import your licenses as needed, and push. No outage, since the management just manages the rules, it doesn't enforce them. You can do this in advance to confirm the rules are all present in their new home, though it's my understanding you can only 'migrate import' on a system once; to import again, you should reinstall the OS on the management VM again. It's a VM, so that part should be easy.
Licensing would probably be the most difficult part. Every license you have using the old management IP would need to be generated again for the new IP, imported to the new management server, and applied where relevant. This would definitely include the license for the management server itself, but would also include any centrally-licensed firewalls. Honestly not too bad, just something to remember.
The firewalls can be swapped in another step. I would personally do them in a whole different window, but I'm averse to changing multiple things in one window in general. If you're sure you want to, they can be swapped in the same window.
I would treat it like replacing failed cluster members. Shut down the old one, bring up the new one with all the same IPs as the old firewall, establish SIC, push policy. Force a failover, then do the next one.
Changing a management server's name is where things get complicated. The management server has an internal certificate authority it uses for SIC which is signed to its name. To change the name, you have to reset the internal certificate authority. If you need to change the name, you'll have to discuss it with the TAC, as the steps involved are dangerous to the management server.