There’s still one I’d have to go and look it up because I use it myself from time to time. It’s standalone and it works best with single instrument tracks.

However, you can use free openvino audacity plugins to strip a song into its individual tracks and then use other programs to convert those tracks to MIDI and then import them into a midi editor and then recompose them as needed.

It for now is incredibly janky and is an awful lot of work and is not clear and straightforward at all but it is feasible, and I say feasible very slowly and methodically to communicate that it’s feasible in the way that you could feasibly build your own house on unclaimed land without spending a dime just using stone tools that you made yourself and wood that you personally harvested from fallen trees.