Aw yeah, sugar wafers! They require something like a waffle cone maker to get that kind of browning and crispness all around. There's lots of hacks that start with tuilles or other type of batter that's baked or griddled, but the real talk is that you def need an iron to press the batter out so thin, and brown it so perfectly.
I don't know if it's good news or bad news, but I have a waffle cone recipe coming out next week, and it will be a small tweak or two away from that kind of sugar wafer. I've been playing around a lot!