How can i get this result ?

Images for each layout are loading separately. You can try to add all these sprites onto the Loader layout to "cache" them, but I am not sure if this will help.

I still think it's not the image size that's causing slowness.

Try this test - create an empty project. Import all 600+ sprites, put them all to a layout, but don't add them to a container. See how fast this layout will load?

if i remove container items it also removing from another layout

i tried to import every sprite to loading layout and preview it

A black screen for few seconds (seems like loading in black screen) and no loading bar process and Just appeared completed loading then it did not load again for another layout.