You can use an acf/prepare_field filter to alter any setting of a field.
To see setting of a field to know what you need to change use the ACF export to PHP tool so that you can see the structure of the image field.
You would need to conditionally change the right setting based on the post type being edited. I don’t have any code handy for hour you would do this. You may need to look at the values in $_GET when adding a new post.
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