I am still not sure if I understand what you need. If you have a Smart Object, which occurs multiple times in your PSD, you can double-click it, put all your s

I am still not sure if I understand what you need. If you have a Smart Object, which occurs multiple times in your PSD, you can double-click it, put all your screenshots inside it and save it. Then you can simply switch the visibility of layers inside a smart object. Using Photopea would require running it in a browser window, it would be hard to connect it with your terminal.