It doesn't come up often. But has been requested before. You would probably have to make something yourself.
I tend to use mixers for practice. Since there is headphone jack on a mixer.
And use computer plugins for more options
Likewise you could use the DI out on the head with a mixer. And I believe master volume could remove power amp signal. So you wouldn't have to unplug the cabinet. monitor with headphones through DI into mixer
Otherwise effect send to mixer if master controls DI out volume.