Batch saving new images from auto crop & straighten

I have a batch of scanned photos from an album to perform auto crop & straighten on. I want to automate the process, creating an action that opens a source file, performs auto crop & straighten, and then saves all created new images (in tabs) as JPEGs to an output directory. Basically, I have tried two ways:

1. After crop & straighten, use "close all" and click save when asked for each image, and then specify the folder and JPEG settings for each image. Problem here is, the action then becomes specific for how many pictures there have been created out of a single scan file, and this number may vary.
2. After crop & straighten, use the image processor to save all open documents with a specified folder and JPEG settings. This would basically be what I need, but it doesn't work, because apparently it only does on open tabs with preexisting documents, but not newly created ones as they haven't been files before. When I try to do this, I only get the error message: "There were no source files that could be opened by Photoshop", followed with a list of the open tabs.

For the record: Neither do I want to perform an extra action on the images nor have I selected any in both ways. I tried different output directories, but didn't change anything.

Is there any workaround to be able to fulfill my needs here?

(using Photoshop v21.2 on Mac OS 10.15.5