This is most likely a pixel alignment problem, you need to do the steps mentioned in this page 2D Pixel Perfect | 2D Pixel Perfect | 5.0.3
you dont need to use pixel perfect camera for this to work, you only need correct orthographic scale.
Which misses point 2 I mention below:
- In every single one of your sprite assets, set the pivot unit mode to pixels
- In ever single one of your sprite renderers, set sprite sort point to pivot(though you can skip this if all of your sprites have even number of width and height, I’d still recommend doing this)
- set up your grid snapping correctly and enable it(should be blue). My ppu is 128 so I just set the grid size to 1/128
- Select every gameobject in your scene and hit align selected/all axes
Some more on pixel alignment and smooth camera: