Needing help renaming random text trailer files quickly if possible



Okay so here goes I want to rename a bunch of trailer files downloaded from YouTube for my Kodi I normally will use Bulk Renamer Utility and then do file by file until I found out I can actually use a script inside notepad++ and then save the file as a bat file and rename a bunch of my movies quickly. But that works great for the movies since there mostly all from the same site. But with YouTube the titles of the files are the titles of the YouTube video which means I have to change each line one at a time is there a faster way of doing this instead of copy and paste for every single movie every single time I need to add a trailer file to the main movie file.

I will be editing the main movie and metadata first and then adding the trailers to each file once they are renamed correctly or is there a way to have a program change the file name for the trailer without me needing to edit it myself. Like if I was to place it inside the folder and have -trailer.mp4 at the end of the file would there be a way to change the text before the – to match the movie title name.