My mom made me POA with my brother as next if I was unable. She moved closer to him. Can I pass it to him? What is the legal route?

I agree, you are unable to perform the duties, so let brother take over. You may want to see if you need to write a letter to say this. That because of the distance you are handing over primary responsibility to your brother but will step in when he is unable. Have it witnessed and notarized. Check with a lawyer or legal aide to see if this is how it should be done. Check the POA, it may give instructions on how to handle it.

Other members maybe able to give u some input.

Mmluisa, yes, since both your names are in the Power of Attorney, you can bow out and let your brother take over.

I wouldn't have your name removed and a new POA made. Heaven forbid if something happens to your brother, at least you would be able to step in to made decisions for your Mom.