Music app of iOS 12 on iOS 13 Is it possible to have the music app of iOS 12 on iOS 13, because the interface where the queue can be accessed only by pressing a button rather than scrolling/swiping down is very annoying.

Open to Jailbreaking the device for the same.
Apple uses code signing to lock all their apps to the latest OS version. If you were to jailbreak your phone it might be possible to replace the Music app from a previous version but it would likely cause instability. 

A more reliable solution would be to roll back your phone to OS 12. But you’d be trading off the new features from OS 13.