As well as point and graphic cells, Microstation has parametric cells, in which the exact geometry of the cell depends on user input. More info at https://docs.bentley.com/LiveContent/web/MicroStation%20Help-v19/en/GUID-0D6C4E6A-2E0E-4004-B464-4B58440FA893.html
Would be great to support this in the future!
(FMEENGINE-78421)
