Change PDF page size (and creating an action to automate it)

I'm trying to create an action to change page size of a whole folder of PDFs (and save a copy without altering the originals) from their original size (usually 9x12 in) to US Letter (8.5 x 11 in).

Using the Crop tool failed already outside of the action, saying that the page could not be resized. Besides, adding the Save action at the end since I want to save a copy of the original files, not change them asked me this for each file:

This didn't happen for other actions I created, it was just working as intended, opening > processing > closing the file and moving on iteratively. 

Now, I should use the Print Production > Preflight > Scale to specific size function but when I go to try to create an action for that, it doesn't work. How can I succeed here?

It seems to me that resizing PDFs should be a quite straightforward action in 2025 but, instead, I am not finding quick, reliable, repeatable ways.

Thank you for your help.