What you are asking is a bit much for a simple batch file (i'm assuming you are using windows yes?) espectialy when you said that you want to be able to fetch data from the web. The easiest approach to this would probably be to use a a scripting language like python. Have the batch file simple kick off the program. Python has a lot of ready made libraries for helping you do exactly what you are asking for there.
But, and i'm not 100% certain on this as I'm not a windows batch guru, but I don't think what you are asking is even possible in windows batch. each line of a batch script is an entirely independent command and so it is hard to share information needed to do what you are describing. It could probably be done with Linux Bash files, but that would probably take far more effort than just using a language that is designed for that sort of thing. batch and bash really aren't.
some example code in python
subs = os.listdir(path_to_your_files)
Then make some function that finds all the movies in that folder, and its sub folders recursively then it isn't hard to parse out the information from the name as you want to do.
An IMDB python api can be found here
I'm not familiar with atomicsparsely, but if worse came to worse you could make the commandline calls you need as python strings and then call them from python. not fantastic, but it would certainly get the job done.