(DISCLAIMER) There is a better converter with hold notes here. https://scratch.mit.edu/projects/666734314/ Current version: V1.4 Yeah I basically ripped the debug menu from Scratch's Smooth Saturday and put it here.
@SquigglyTuff heres a small tutorial because people have trouble with this. first get the mod you want to get the song chart from, go to data, go to the song, open up the .json, copy everything inside of it, go to the project, press load song from json, paste it in, wait for it to finish, once it finishes, go inside the project and right click on the chart list, press export and you are done.