How can I combine HCM and Projects subject areas in OTBI

Summary:

I would like to know if it is possible to combine HCM subject areas with e.g. Projects subject areas in OTBI.

Content (required):

Hi!

I'm creating a rather large OTBI, which takes data from HCM and the Projects module in Fusion Cloud. In HCM I would like to use the Workforce Management - Work relationship Real Time subject area, and combine it into my analysis with a Projects subject area: Projects Cross Subject Area Analysis. However once I use the HCM subject area the fields just turns blank with no data inside. Even though I under the Advanced Tab inside the OTBI analysis ticked of the box  under