I'm looking for a specific pedal

Hello guitarists,

I'm looking for a pedal that allows me to hear my guitar from both the AUX headphones and the amp at the same time without using a mixer.

I even posted on r/guitarpedals but no one answered. I wasn't looking for pedals like the Boss Amp & cabinet but something cheaper, I just need to hear myself from the headphones and the amp, that's it.