Mac Book Pro - Photos program

Are you talking about a slide show? If you do a simple slideshow using this:

Then you get a quick result, but you don't have many options.

But if you make a slideshow using the File>Create command, like this:

You get more options.

You can change the "themes" (the transitions), the music,

and the duration of images.

I hope this is what you were asking....

Most parts of Photos cannot be scripted. It is not possible to use Apple script to add title slides in a slideshow.

I am using two different approaches to create slideshows with titles:

1. Running an Apple Script to show the photos in an album as a slide and step the album slide by slide. And whenever a new slide is shown, a notification will appear in the notification center to show the title, the location, and the date. See this old user tip: Script: A Slideshow With Titles and Loca… - Apple Community I have not yet tested it on Sonoma.
2. The other method is to avoid the slideshows in Photos and to use the photos as a screensaver. The free ArtSaver (https://mac.dailydownloaded.com/en/screensavers-wallpaper/screensavers/21434-artsaver-download-install) can show the photos using the metadata as captions.

And when I am having a lot of time, I create my slideshows as a Keynote presentation. Then I can add any text I like and control the animation effects and, sound effects and the sound track.

Batch operations are very limited. I haven't needed batch cropping, and I'm not sure I've seen scripts for that. Captions, too, seem difficult, and slideshows in Photos are not especially versatile. When I've wanted to do a slideshow with titles and such, I've exported the pictures and used 3rd party apps. I've used GraphicConverter ($40) for that and for many others things-- it does slide shows, batch file operations, accesses metadata, and has some editing tools not available in Photos, so a number of us use it a lot. But it can't be used inside of Photos--only on pictures in Finder.

Since you're just switching from iPhoto to Photos, you may remember (drat! memory-- what was it called?) by FatCatSoftware. When the switch occurred, their program wouldn't work, and it was a great loss. Now they have  PowerPhotos ($30), which is very useful-- you should check it out.

iPhoto Library Manager?

ILM! Thanks-- it's funny what 7 or 8 years will do to your memory. Well, mine, anyway...