No. A power of attorney grants legal power to a named agent (person) to handle the financial decisions of the person who signs the power of attorney (the grantor). This document is no longer effective when the grantor dies.
Your will or trust will not override what is named in the beneficiary designation on a life insurance policy, annuity, or retirement account (like an IRA or 401(k) plan).
Probate is the legal process through which a deceased person’s estate is properly distributed to heirs and designated beneficiaries and any debt owed to creditors is paid off.
Having a trust allows you to have more control of your assets if you’ve become incapacitated. Some of the benefits of a trust are: avoiding probate on your assets, reducing estate and gift taxes, protecting your assets from creditors and lawsuits, having the ability to name a successor trustee who’ll have the power to manage your trust after your passing, etc.
A basic revocable living trust will not reduce your estate taxes; its intended purpose is to keep your property out of probate court after you die. An A-B trust is a joint trust created by a married couple for the purpose of minimizing estate taxes. They will have the ability to leave some property to their children. But allowing the surviving spouse to use it during their lifetime.