By default on a fresh new installation you will get an error when trying to move VM's between two Hyper-V hosts.
Something in de line of "no credentials are available in the security package Hyper-V"
If I remember correctly, this has to do with Microsoft changing the way the servers communicate to make it more secure. Sadly Microsoft doesn't automatically configure this for you even in the 2019 version of Hyper-V.

Assuming your Hyper-V hosts are domain joined, follow these instructions to configure your hosts to allow move/migration between them.
I'm not even sure if this error even exists when you have workgroup Hyper-V hosts...

1. Open Hyper-V Manager
2. Rightclick on your Hyper-V host and click Hyper-V Settings
3. Go to Live Migrations
4. Make sure a checkbox is set on Enable incoming and outgoing live migrations
   Also configure it for Use any available network for live migration. You can set it to Use these IP Addresses for live migration if you have seperate move/migration traffic from production data
5. Expand Live Migrations and click on Advanced features
6. Set the Authentication protocol to Use Kerberos and click Ok to save the settings
7. Login to tyour Active Directory server and start Active Directory Users and Computers
8. Find the computer accounts for your Hyper-V hosts and open both their properties
9. Go to the Delegation tab
10. Set all Hyper-V hosts to Trust this computer for delegation to specified services only
11. On both Hyper-V hosts add the CIFS and Microsoft Virtual System Migration Service service types for each Hyper-V host it needs to connect to.
    For example. If Hyper-V host #1 needs to migrate to host #2 and #3, then you will have 2 CIFS and 2 Microsoft Virtual System Migration Service entries for both hosts. On Host #2 you configure the same thing for Host #1 and #3, etc.
12. Login to all your Hyper-V hosts and start a command prompt
13. Enter the following command on all your hosts: KLIST PURGE -li 0x3e7
    What this does is that it clears all existing Kerberos tickets and requests new ones, an early refresh if you must. You can also wait 15 minutes... same thing really.