Different source of authority
A power of attorney acts under an authorization during the grantor's lifetime according to applicable law; an executor or estate representative acts in estate administration after death under a will and/or court authority.
Terms vary
Some jurisdictions use executor, personal representative, estate trustee or administrator.
Documents should not be conflated
Naming one person in one role does not automatically give that person every other authority.
Local estate law controls
Use current probate/estate guidance in the relevant jurisdiction.
This page provides general educational information. For a real agreement, dispute, court filing, estate matter, debt problem or authorization document, check the current rules that apply where you live and obtain qualified advice when the consequences are significant.