Evolution reports show the evolution of data given some dimensions such as project name, analysis name, report name, etc. When one of these dimensions is different, the studio can not find a direct link among the data.
When you import an evolution report from one project in the Studio to a different project that has a new name, this report will not show the history of the evolution of data in the old project. If the project name changes, no link is established between the old analysis results and the analysis results in the new project. So the report starts at a new point in the new project and shows any evolution of data from that point onwards in this new project.
Two options are available for you to migrate evolution reports between projects and keep seeing the evolution of data through these different projects:
either, import the evolution reports into a new project that has the same name of the old project. For further information about creating a local project when launching the Studio, see the Getting Started Guide.
or, use a different name for this new local project but customize the JRXML template and use it to execute the evolution report.