In order to create a Photoshop shortcut using ACTIONS which DOES NOT add the word “copy” to the filename, you have to first flatten the image. Once the save is done, you can step-backwords to unflatten the image:
1. Create a new action from the Action Dialog (Alt-F9).
2. Be sure to assign the shortcut key at this stage.
3. Record the following actions:
a. Flatten Image (from the Layers window)
b. Save as > JPEG – ensure Make Copy is not ticked
c. Finish saving the image
d. Edit > Step Backwards.
The latter will undo the merging of the layers.
You are done. The images is saved as JPEG and if there is an existing file it will have been overwritten.