Create new divisions of each sport allowing hormone/substance-of-any-kind enhancements without the separation of gender. If one wishes to transfer back to the non-enhancement version of the sport, they must wait five years after their last dose and participate in the gender of their physical genitals. Got a dick and tits? You're a male! Got a puss and no tits? You're a female! Why make it any more complicated? Apply this across all ages. Done.
But of course, that will split the money such that more money goes into the enhanced sports than non-enhanced, causing a squall among those that profit from current sports and wish to maintain traditional sport.