Subscription Change Directory

Hi

I want to change a SubscriptionA from AzureTenantA to AzureTenantB via Subscription Change Directory.
UserA has The Role Assignment Owner on SubscriptionA and is also a Global Admin on AzureTEnantA.

I have added UserA as guest in AzureTenantB. What kind of permissions do I need to assign UserA in AzureTenantB?

I have read the:

https://docs.microsoft.com/en-us/azure/active-directory/fundamentals/active-directory-how-subscriptions-associated-directory

Giving UserA Global Admin on AzureTenantB enables me to use the Change Directory (I can see the destination directory now). But is Global Admin required?

brgs

Bjørn Roalkvam