EPBCS to EPBCS Integration

Summary:

I have to create two EPBCS applications for budgeting and then consolidate the budget in one application. The application will have same number of cubes but the dimensions will be different in cubes.

I have a query that for integration purpose the cubes should have either same or different names in both applications?

How can I integrate these two planning applications?

Both applications have data in different currencies. Do i need to translate it in the target application?

What is the difference between integration either through Applications > Data Exchange or Tools > Connections?

I need to understand this to configure before the second application to avoid challenges.