Is the source file being copied static (i.e. always the same file)? Which is then applied to the several hundred different files?
If so you can do this fairly easily with a batch action.
No it will be a 1 to 1 sort of thing one folder of images backgrounds in color blending mode need to be put on another folders set of images
OK… So is there a logical sequential pattern to the files in Folder A vs. Folder B?
How will a script know how to “pair up the files” correctly from two different source folders?
Will the files have exactly the same name in each folder?
Will the names vary, but have some common naming such as a sequential number –
Or perhaps metadata such as creation date, keyword etc?
I am not a scripter, however I believe that these are the sorts of challenges you will face.
To illustrate visually, here is what I am trying to say:
Yes exactly the names of the images have the same starting sequence number