I am POA for my dad. My brother took my dad from nursing home had himself put as irrevocable beneficiary on his life insurance and his home.

I’m confused, was your dad living in a nursing home and now he’s back in his own home? If your father is mentally competent and okay with what your brother and his wife are doing, living in his home, using his money, then there’s nothing you can do about it. A competent adult can have whoever they want in their home, do want they want with their money, even be treated poorly. Sadly, it’s far too common. When you see abuse it should be reported to Adult Protective Services in your area, this will set off a chain of events designed to help your dad, but if he defends his son and daughter in law, it’s likely not much will happen. As for selling the house, POA only kicks in when your dad can’t make his own decisions, if he’s competent that’s for him to decide. He clearly shouldn’t be living this way, I hope he can be convinced to change the picture

I say call adult protective services and report elder abuse. Do it discreetly. No one should be bullied.

You have to sort out who has legal authority to make anything happen. You wrote that your dad is "cognitive". How do you know? Why was he in the NH to begin with? Was he in AL? Has he ever had an actual cognitive exam given by a physician so that it's in his medical records? PoA means you act in your father's best interests when he is no longer able to. You may not like what's going on, but if you cannot prove your father was cognitively impaired prior to him leaving the NH and making your brother the trust beneficiary, I think you will need to lawyer up if you think he is being abused/bullied by his son. Others with actual legal knowledge will soon provide more insight.