Nate wroteThere isn't, sorry. We've not encountered the need before. Is there a reason you want some layers to be twice as large as needed in the PSD?
Currently I only use the Spine export script once, to initially place the assets in place, then I use Adobe Generate functionality so I can set individual scaling of different assets. eg "25% sky_gradient.png". It's also much quicker output updated assets. It's also capable of treating a layer group/folder as an image to out put. This allows our artists to keep the art more editable for tweaks.
The individual image scaling is quite useful and I use it all the time for assets with low frequency details. Like clouds or gradients. I should add that I some times use non-uniform scaling of things like a sky gradients, where I set the horizontal scale to say 10% but keep the vertical to 50%.
Being able to out put folders as images is also versatile as I don't need to flatten them before hand.
Generate is pretty good, I can even work in realtime, switch back and froth between PS and Spine and see the image update immediately because Generate is so quick and seamless behind the scenes.
But the PS to Spine script could really make use of the individual scaling and export folders as images functionality.