Is it envisaged to have a dashboard by project to identified in the same page (values + visuals diagrams) :

- Tasks in progress with % of progress
- Risk identified
- % of Progress of all subprojects
- Count of Exigences and progress (accepted, rejected, in progress, closed)
- Count of Uses cases and progress + Planned date start plan and target
- Count of Issues

No it is not as project dashboard will differ for everyone. Some don't care about risks, some don't care about requirements, some will focus on tickets...

Or, can we use plug-in screen customization to update page of project and consolidate all datas followed in other forms

No.
Screen Customization will allow to add fields, but not to add consolidated data.