I'm tired of going up and down and left and right can't I just go one direction?
No, eggs will not hatch in the Festival Plaza because it doesn't count the steps you take there.
Source: https://m.bulbapedia.bulbagarden.net/wiki/Festival_Plaza#:~:text=Steps are not counted in Festival Plaza, so,hatch and Repels will never wear off there.
However, the place I use is the little square just below the Nursery in Paniola Ranch. You go in there, hip on Tauros and just move the circle pad in circles.
Hope I helped!