I mentioned previously how my old bosses properly took the piss out of a guy who wore a full on suit and tie to an interview, it was very mean. They gave him the job though!
When I’ve gone for interviews/meetings at these types of places I just try and dress a bit smarter than I normally would, because well I think it’s silly to wear something that you wouldn’t normally ever wear and it’s good to show your personality a bit. So yeah, I’d say some cool trousers with a shirt and no tie or a shirt with a nice jumper over the top would be grand. I’d say even wear trainers if they’re newish/clean and not scaffy looking… if not then smarter shoes to be safe.
EDIT: I’m sure you’ll look great! Good luck to you!! 