I will be migrating a client from on premises Exchange to Office 365. Part of the migration is upgrading the Office version on their Server 2019 Citrix servers to Office 365 apps. What are the currently required FSLogix settings to get licensing to work properly?

None. The defaults work fine

License Token Key is stored in the profile. As @Aaron Parker mentioned, there are no special configurations needed. https://learn.microsoft.com/en-us/deployoffice/overview-shared-computer-activation

Just make sure you are using shared computer activation for O365 apps

Thanks to all. Just seen many posts recently regarding activation issues so wanted to confirm.