Ability to create Sub Spaces

Ability to create a site-wide Confluence Cloud navigation.

User example:

the use case is that we have projects that need its own "sub space" in a space.
The hierarchy would be like this:
Project 1 is a sub space and has individual pages of Requirements, Development, Delivery, etc
Project 2 is a sub space and has individual pages of Requirements, Development, Delivery, etc
and so on Project 3, etc
As you know a Space cannot have the same page title. But we want to be able to use Requirements, Development, Delivery, etc as the top level pages for each sub space.

*Marketplace example: *https://marketplace.atlassian.com/apps/194/subspace-navigation-for-confluence?tab=overview&hosting=cloud