RipX can do stem separation and allows repitching notes in the mix. If that is what you want to do it is great. I find moises (https://moises.ai/ https://moise

RipX can do stem separation and allows repitching notes in the mix. If that is what you want to do it is great. I find moises (https://moises.ai/ https://moises.ai/) to be easy to use for the tasks I need to do. It allows transposing or time scaling the entire song. It does stem separation and has a simple interface for muting and changing the volume on a per-track basis. It auto-detects the beat and chords. I'm not affiliated, just a happy nearly-daily user for learning and practicing songs. I boost the original bass part and put everything else at < 10% volume to hear the bass part clearly clearly (which often shows how bad online transcriptions are, even paid ones). Once once I know the part, I mute the bass part and play along with the original song as if I was the bass player.