There are a few ways to batch Photoshop shirt mockups in Photoshop. One way is to use the “bulk export” command. This command exports all the layers in a file, including the layer masks. You can then use this file to create a new Photoshop document, and import the exported layers into that document. Another way to batch Photoshop shirt mockups is to use the “select all” command. This command selects all the layers in a file, and then you can use the “copy” command to copy all of these layers into a new document.