So I have my base icon PSDs that I apply to my icons and tweak as needed. Lately, though, manually dragging the layer masks from my master file to the individual icons had been hell on my wrists.

Is there a way to automate the process of dragging the layers from one file to the other? I know I can use a custom action with the 'file > automate > batch' function, but that would require me to remake each PSD from scratch in order to record the custom action, so I'd like to avoid it if possible.