What was the point in Elle Macpherson's character?
Well, besides trying to dispel the notion that Bruce Wayne was you know...:
https://en.wikipedia.org/wiki/Homosexuality_in_the_Batman_franchise#Joel_Schumacher's_films
https://whatculture.com/film/10-weirdest-ever-cameos-in-batman-movies?page=2share
Though it's not uncommon for Bruce Wayne to have a glamorous, beautiful woman on his arm, Joel Schumacher's Batman and Robin took this to parodic levels by casting legendary model Elle Macpherson as Wayne's (George Clooney) well-to-do girlfriend Julie Madison.
Macpherson's role in the movie ultimately extends to little more than proposing to Bruce and being awkwardly rebuffed, before basically disappearing out of the movie entirely.
Most of Macpherson's scenes as Julie were actually cut from the final film, including being stabbed to death by Poison Ivy (Uma Thurman).
The part was ultimately whittled down to a totally bizarre, perfunctory cameo that couldn't hold a candle to Vicki Vale (Kim Basinger), Selina Kyle (Michelle Pfeiffer) or even Chase Meridian (Nicole Kidman) in the prior Batman movies.
Given that Julie was a relatively prominent love interest in the earlier Batman comics, it's a pretty disappointing treatment.
That's not to ignore the fact that the little of Macpherson's performance that remained was as stiff as a board. Of the many baffling decisions Schumacher made on this movie, this is right at the top of the pile.