billing event for cross charge projects

Dear Experts,

Can we created a manual event in project billing against a cross entity enabled project?

I want to create it like we do cost booking from other entities for a Cross charge project.

If we can, we are the setup we need to ensure to create such cross charge proj event?

I did all setup and tried to create a project from a cross charge OU but I cant find my project which I supposed to see.

Or, enabling Intercompany projects billing is only option to achieve functionality?

Thanks

Venkat