To use a computed variable material in downstream analyses, you must provide the field data. You can do so by adding an External Data system to the project schematic.
The external data needs to specify, for instance, the spatial distribution of the fiber volume fraction for a workflow with a variable UD material or the distribution of the relative density (volume fraction) for a workflow with a variable lattice material.
If you are using ACP, you do not need the External Data system. Fields can be directly defined in ACP. In particular, the shear angle (due to draping) is directly computed and made available by ACP. In this case, the workflow is the same as the constant material workflow.
See Analysis Using Variable Material Data for more information on analyses with variable material.