Save Selection As

You could save a step by making an Action that does these 4 things:

1) Image > Duplicate (safer, in my opinion, than relying on undo)

2) Load Selection (via command/control-clicking a particular alpha channel for the selection)

3) Image > Crop

4) Delete the alpha channel/s if you don't need it/them.

Then all you'd have to do is run the Action followed by SaveAs for each journal page. As long as your shape is consistently in the same alpha channel, this should work.

And thanks for making this feature request; it was only by reading these replies that I became aware of Save Selection As and Export Layer directly to transparency png, both very relevant to me.

I mainly work with original PSD files.

1. Crop and commit with Enter.

2. File > Export > Export As (PNG or JPG).

3. Export All to your preferred location.

4. Close the PSD file.  When prompted to save changes before closing, hit NO.

Hope that helps.

@JMLBloodLite 

I appreciate that this is an "idea" or feature request. If you need this functionality now, you can copy the selection to a new layer. Right-click on the new layer and select Export As. Or copy the selection to a new file and save that file.

A custom script could be created to automate for other file formats.

@JMLBloodLite not sure is this helps in your situation, but there is a save selection option in Photoshop