When did it crash

loading into a world worked fine however when right clicking on a created atlas to open it the game crashed

Minecraft version

1.18.2

Mod loader

Fabric loader 0.14.9

Loaded mods

• Antique Atlas
• Architectury
• Cloth Config v6
• ESSENTIAL Mod
• Fabric API

Latest log

https://paste.ee/p/TLdvl

While it affects the atlas, this crash seems to be caused by the Essentials mod. You should report it there.

FYI the reason for this issue stems from Essential (and presumably also the mod in #406) adding a mixin accessor for Screen.children which by convention is List<...> getChildren().
That accessor is then implicitly overwritten by atlases' completely unrelated GuiComponent.getChildren. That method has package-only access and therefore throws an IllegalAccessError when the third-party mod tries to use its accessor.

If you want to, you could change the name of that method to avoid such conflicts in the future. But the only real fix here would be to change Mixin such that e.g. accessors are always name mangled.
Essential will also include a fix for this in its next version. So if you wish to reproduce this in the future, you'll have to start MC with -Dessential.branch=1.1.0.10 to use the old version.

Thanks for sharing. I'm going to close this then.

For future reference: The solution is to update Essentials mod.