Obviously, its mirror won’t look nice. All I need to do to fix this is flip it horizontally, but there doesn’t seem to be a way to do this by messing with the Parallax Layer proprieties. Would I need to make a script to fix this or am I missing something?
“Mirroring” in a ParallaxLayer doesn’t actually mean that it’ll be flipped horizontaly. I guess it’s a wording issue. You’ll probably need to make a script to fix this.
Alternatively, you can use a TextureRect with the texture’s import settings as repeat → mirrored and Expand on and Stretch Mode Tile. You’ll need to set the TextureRect’s size since turning Expand on will cause it to disappear. But that’s combining Control nodes with Node2Ds which might cause issues later on.