After a lot of work, I finished version 2 of the story box. Same cartridge system, same buttons, but I added a screen to navigate through the songs. 

I used:

An ESP32

A TFT screen

A MP3 player

A USB interface

A battery charging Module

The ESP32 reads files on the USB stick when inserted, displays an image located on the drive.

I also added + / - volume buttons that where missing on V1