Invite guests to Viva Engage Community

I am looking into using Viva Engage but it is a deal breaker for us that guests with non-microsoft accounts cannot be added. 

It looks like the old Yammer used to allow external users to join? but the new Viva Engage does not?

I have read articles about the new B2B guest framework https://learn.microsoft.com/en-us/viva/engage/work-with-external-users/collaborate-guests-external-viva-engage-community

What I am trying to achieve though is allowing personal accounts, gmail, hotmail, etc

Our use case is that we have a company community, but would like to invite a small number of guests into our community prior to them joining our team to give them a feel for how the business operates. 

I would be happy to assign purchase and assign licenses, but there is no easy way for non Office365 admins to do so. It would also cause friction to ask a new person that is not part of our business to use a new MS email account. 

Ideally this is how I would see it working

1. Just allow guests to join with personal accounts. Community admins can just type in their email and invite them.
2. We could have a pool of available Viva Engage licences. Community admins can invite a guest via their personal email address and assign an available licence.