Demucs is one of the best ways i’ve found for splitting stems for transcription. There are a couple of ways that you can use it (both free):
Easy way with an installer/gui: https://ultimatevocalremover.com/
Demucs - the hard way, for nerds: GitHub - facebookresearch/demucs: Code for the paper Hybrid Spectrogram and Waveform Source Separation
But wait; there’s more! There’s this too, Guitar2Tabs from Klangio which is not free but has some free/trial functionality: https://klangio.com/
