What DGSketcher has shown you is applicable to both beams and columns.
You place a segment (along the length for beams, height for columns) for each profile that is different.
Each segment can be a completely different size from the previous one although they all share a common axis line along the entire beam/column.
Using complex profiles for the segment, you can basically create any cross section shape you want - even two tenons.
To make one tenon short and the other longer, you want two segment - one with two tenons and one with just one.
The length of each segment can be fixed or adjustable proportionally with the overall length of the beam/column.
You can even use modifiers in the complex profiles so you can adjust the shape of each segment and each segment can taper to a larger or smaller segment next to it.
Maybe watch some videos on the Archicad YouTube channel.
Scroll down to the ones for version 23 - that is when the segmented beams and columns were introduced.
They won't show you every possibility, but they should give you a good idea.
If you can show some images of what you need, I am sure we can say if it is possible or not.
Warning, you will end up with a lot of complex profiles, so name them carefully so you can group them to make them easier to find in the list (they can be renamed at any time).
Segmented columns and beams may not be quite as good as a well scripted and adjustable object.
But you don't need to know anything about GDL scripting.
PS holes can also be placed in beams (not columns) and even the new opening tool can be used (again for beams not columns).
Here are a couple of example columns I have posted previously.
Each image is just one segmented column with nothing else added.
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Versions 6.5 to 25
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