As I announced a couple of days ago, I have decided to start making some charts for the rhythm game Etterna with the purpose of converting Undertale's entire OST into an Etterna song pack. Out of 101 songs, I have completed 4 so far, and I am definitely planning on making more!
On August 6th I will also release a preview of the pack on the Etterna servers, so stick around for when it'll come. I will make sure that a link is presented on this specific post on the mentioned date.
EDIT (08/06/2021): If you wanna see what's up with this pack so far, I have just released the beta pack on Mediafire at this link: https://www.mediafire.com/file/7y72cbw2mamvsbb/Undertale_OST_%2528speedrhythmics%2529.rar/file
It is a beta, so any sort of criticism is appreciated. Have a great one fellas!