Hello there!
I am working in Revit and trying to export this later to IFC:

In my model, I already created 2 categories “boundary type” (physical / virtual) and "boundary location (external / Internal). Now I have assiged all elements including spaces as physical to be able to export the relation between elements, but this is still not visible.
The Space Boundaries are there but the RelSpaceBoundaries not.
So, I am trying to achive that my available Space Boundaries (SB) to be Physical Related Building Element (RelatedBuildingElement).
When I export my IFC says Virtual/Physical and where the related building element should be there is a “$” instead.

Do i have to create a shared parameter to generate this relation between element, or how can I achive this?

I hope my questions is clear enough.
Thank you!

This question is better posted to Autodesk. For example in their Revit IFC-exporter repository on Github. There are already a couple of open issues related to space boundaries and if one matches your problem, you might want to add that instead of creating a new issue there.