Sharing a Custom Report will share the report configuration and data included in the report.

Only configuration data is shared through the Solutions Gallery. When you create and share an asset, your personal information and Analytics data stays private in your account. And when you import an asset from the Solutions Gallery, only the template is imported into your account. For example, if you import a Custom Report, you can use that report to analyze the data in your Analytics account, not the data from the person that created the report. You can share Dashboards, Custom Reports, Segments, Goals, and Custom Attribution Models in the Solutions Gallery.