For example, we have a Team consisting of individuals from 4 companies, each company have potentially multiple domains.
We want the following:
- When we schedule meetings we want to see each other's availability.
- Access to Teams functionality
- Shared files storage
- Channels and Conversations
- Chats and Group Chats
Update 1:
When you are added as a Guest you do not have a Calendar in the toolbar. You cannot schedule a meeting. This is not good for collaboration. The below image is what it looks like when you are a Guest.
Update 2:
It appears that this currently is not a supported feature. This really inhibits productivity and collaboration. Vote here if you agree.