I think it's the only honest interpretation of our sources about them.
The problem is that the aforementioned source is the infamously unreliable Historia Augusta which is full of fabrication and was written more than a century after Elegabalus died.
Trans or not, Elagablus was a teenager used as a pawn by their family in a dynastic political game which got them assassinated at 18 years old.
ao3 author: *writes the most devestating ending to a 150k fic that simultaneously calls back to the first chapter and beautifully wraps up every theme in a few paragraphs*
also the ao3 author (in the endnotes): uwu i never know how to end these things T_T