Washington Revised Code Title 11. Probate and Trust Law § 11.120.030. Applicability

(a) A fiduciary acting under a will or power of attorney executed before, on, or after June 9, 2016;

(b) A personal representative acting for a decedent who died before, on, or after June 9, 2016;

(c) A guardian acting for an incapacitated person appointed before, on, or after June 9, 2016;

(d) A trustee acting under a trust created before, on, or after June 9, 2016;  and

(e) A custodian if the user resides in this state or resided in this state at the time of the user's death.