Correct, there has to be a single "normal" belt between two sorters or a loader and a sorter, as they are coded to interact with the belts.
Rotation can only be done manually in the GUI (and as I'm not a true coder, changing this is (currently) beyond my possibilities)..
There would be loads of special cases which are very hard to implement. I won't find the time to implement this. Consider it a challenge to place your beltSorters with a normal belt inbetween.