Tapered sections are partially supported in Konstru. By default Konstru will chose the section at start as the default section for the entire frame.
There is limited support for tapered sections from ETABS into Revit: If your ETABS section is tapered the profile can be downloaded into Revit. Make sure the Profile Mapper in Revit is set to "Create New" for the tapered section coming from ETABS. Revit will create a new family containing the tapered profile. By Default ETABS defines tapered sections centered (like in the image below) and aligns both sections to top or bottom depending on the frames alignment settings. Revit on the other hand requires a new family for each alignment. That's why we recommend to use different section names for different alignments in ETABS to get best results in Revit.