Like others said, they’re basically the same car underneath. So it comes down to ergonomics and style; just personal preference, really.
…With the exception of the highest end. The EV6 GT is more like a luxury crossover; think a tricked out Mercedes.
But the Ioniq Ns are batshit crazy track cars. They are fast. As they point out here, it’s the only EV that can lap the Nurburgring without breaking down: https://m.youtube.com/watch?v=HZczpFsv9ZY