Cannot change parent of <variable> because imports and exports cannot change view sets.

When you change the parent of a view, the old parent and the new parent must be in the same view subset, with these exceptions:

A local view can be assigned to a new parent in the export view subset.
An entity action view can be assigned to a new parent in the import or export view subsets when the view IS NOT used in a procedure step.
An entity action view can be assigned to a new parent in the import or export view subset when the new parent IS NOT a repeating group view.

Other guidelines regarding views include:

The parent of a view cannot be changed if the view is protected.
External action blocks have only import and export views.
Work views are not allowed in the Entity Action subset.
Group views are not allowed in the Entity Action subset.
A new parent must be another view; the view being moved cannot be its own parent.