Sharing across M365 tenants

[The_IT_Man]

Hi Guys,

 

What would people suggest as the best method for sharing across multiple tenants, particularly if they all only have A1 licences? I was looking at Multi Tenant Organisation tool in M365 but that looks to require Entra P1 licences for every user. Is that still the most seamless way of each tenant working collaboratively without merging them all to one tenant or is there another way i'm missing?