In CRM dynamics, we can assign an user to only 1 BU. If a user needs to have access to data from another BU it has to be explicitly shared with the user or user needs to be part of access team for the record. These are more record-specific options.
To just have access to data from another BU say 'X' data, an owner team can be created for X BU and then users who need access to X BU data can be added to that team.
This approach works but are there any potential risks one should be aware of with this approach.