Hmm, is there supposed to be much of a difference? I recon, if it was physically possible to make a trumpet sound like a tuba, that would be very popular. And as I understand, that is possible with e-guitar and e-bass, because electronics...
No shame in that. You could start accustoming your ears by searching YT for "bass and drums isolated" and listen to those versions and then the originals and see if you separate the bass better.
Yes, you can use lalal.ai to separate the bassline, then feed that to another service like Guitar2Tabs on klang.io. Also, my bad, was busy and couldn't remember the name of the tab converter.