Save the standard setup at group or organization level: dashboard, table profiles, text aliases and menu. Then all companies and departments see the same numbers, with the same names, in Portfolio and on Home. Projects can still have their own customizations where they need them.
How to set it up
Agree on which key figures everyone should report on, for example revenue forecast, final forecast, contribution margin (%) and variance to budget.
Build the dashboard and the table profile for Portfolio with these figures.
Save them at group or organization level.
Use Text alias at the same level if you want to call the terms something else, for example "Cost price estimate" instead of "Budget".
Give managers access at group or organization level, so they see all the projects together in Portfolio.
Local customizations
The most specific level wins. If a project saves its own dashboard, it overrides the organization's on that project, but not the numbers in Portfolio. Therefore keep the variables at the top level the same, and let the projects only add what they need.