Can I have a POA changed from someone who has Parkinson’s to myself? I am listed as alternate.

As a Person With Parkinson's I am offended that you imply that simply having that diagnosis makes someone unable to properly or ethically perform those duties of a POA.

If I remember correctly, brother has done more than just take a fee for being a POA. He has used Moms money for him and family for personal things.

The POA should have in it that the person holding the POA gets paid. Him taking money without back up could effect Mom getting help with Medicaid in the future. Even if his DPOA is immediate, Mom is of sound mind to make her own decisions. Seems he is making sure everything is changed in his favor. Mom maybe signing because she is afraid of son. OPs previous email says a new will was drawn up by brother and has everything going to him and even wifes family. Why should wifes family get anything.

OP needs to her Mom and take her to a lawyer who can determine if Mom is competent to sign anything. If she is, she can revoke brother as POA and make a new will. OP has been posting since Aug 2021 about brother.

No, you cannot add yourself as active. You CAN report any evidence you have of elder abuse with money to APS. They may file a report that you can take to an attorney and file to have those abusing removed as POA. HOWEVER, your Mom currently lives where the other family lives and apparently they are caring for her? It is not illegal for them to be paid for services. Especially if you Mom isn't independent and does live alone and make her own decisions about who to pay and how much. Not knowing the full details, it is hard to judge this whole matter; only you can decide. Are you willing to take on POA and do this work from states away without the help of the siblings, and against the wishes of your Mom? Have you spoken to your Mom? Does your Mom have dementia, because if she is competent and well she is full capable of removing any POAs she wishes to and appointing the alternates.
I would suggest a family conference to work things out.

POA can be changed but have to go through an attorney and your mom has to say she wants this done. Recently had to do this.

I am pretty sure you have been told in previous posts that only Mom can make changes. As I replied in your previous post that only Mom can revolk and assign a new POA. Your first post was Aug of 2021. Why have you not gone to see Mom and taken her to a lawyer to have her reassign a POA? Now, she needs a new Will. This is going to continue as long as brother feels he is in control. If you want changes you are going to need to be proactive.

Pay for POA - never heard of it. Pay for family care - OK, but should be in a written contract. Have you discussed your suspicions with your mother?

Your brother would have to resign and/or your mother would have to make the change. It is not something you can do on your own just b/c you are designated alternate. Your mother may be perfectly happy to have your brother get a few hundred dollars a month for rides and help and being available when needed. He is there. You are not.

Only your Mom can change the POAs. You would have to be activated as POA if your brother were no longer capable of doing it. Usually a doctor or attorney would have to get involved with activating a POA. Are you sure that they are not doing other things for her, visiting and overseeing her care, handling her bills and finances? Maybe your mother agreed that they should take a "fee" for themselves. I personally think that primary caregivers should be paid, as long as there are sufficient funds. There are also government programs that pay family caregivers, administered by each state. They should also take advantage of those programs, if they are eligible. Will you really be able to oversee her care as well as they do if you don't live in the same state?

They're entitled to be paid if Mom agrees to it. Do you know if she has agreed and for how much?

You can't just take over unless your brother is incapacitated or gives it up. His wife is not allowed to take over for him as I assume she's not an alternate.

Any chance brother would resign? If so he can write a letter saying due to health issues he needs to resign and have two people witness his signature and you’re then poa. Or can your mom write a letter saying she dismisses him and assigns you?