In a theoretical Sidekick/Henchmen swap alternate earth, what do you imagine the characters to be like?

This is just kind of a what if scenario I've been playing around with for a while. Basically, swapping the sidekicks with henchmen and vice versa. I.e. Harleen was recruited by Bruce rather then Joker, or the various Robin's being taken in and being the big henchmen for Bruce's other rogues. Any ideas of what the characters would be like? Or who would be with who? I've mostly been thinking about it from the Batman side but this concept is kind of a whole DC concept