This happens to any object in my project.
Sometimes its black or gray lines
How to fix that?
This happens because the Shader Graph preview ignores alpha, and the transparent pixels in your sprite can still have color in them.
Photoshop, for example, tends to create colored lines and rectangles like this in transparent pixels instead of coloring them black for some reason.
It’s annoying, but I’d just ignore it if I where you, since you won’t actually see it in-game. If it really bothers you, you can use a branch node to set the color of transparent pixels to black. This makes your shader less performant though, so I personally wouldn’t bother.