I couldn’t find a quick and easy way to rename my epubs consistently, so I made something. EpubRenamer does just that and has options to customize it to your liking. I wrote this in java in a couple of hours yesterday. More details at https://pipasoft.com/epubrenamer/ and the source is at https://github.com/brianpipa/epubrenamer
I loved your candy addict blog.. got me through my 20’s! Hope you are doing well and hopefully I can see some updates on the blog soon!