Ir there is enough of the pipe sticking out to grab it with
ViseGrip or similar pliers, lock the pliers on the pipe and then
use the pipe wrench to take off the hose bib. I don't think you
can do what you want without using TWO wrenches, one on the pipe
and one on the hose bib.

ViseGrips are a fine way to destroy the pipe. Use a proper pipe wrech (aka
monkey wrench). They're designed to increase their bite on the material as
it's turned. Versus visegrips not only gouging the hell out of the pipe but
potentially crushing it out of round the process. It's possible to misuse a
monkey wrench but not nearly as bad a visegrips.