If you are modeling a structure using applied or generated loads and also applying shear line forces manually via Load Input view, for example to model the effect of an adjoining structure, the shear line forces are incorporated into the total loading on the level on which the forces are specified, thus transferred to the level below via rigid diaphragm analysis.
However, if only user-applied shear line forces are applied, there is no vertical transfer. It is assumed that you have made all the torsional analysis calculations yourself, and are using the program only to evaluate shear wall strengths on individual shear lines.