Though Washington does not have a stand your ground statute, the state supreme court has held that there is no duty to retreat before using force in public.2
Stand Your Ground in Washington.
When there is no reasonable ground to believe that a person is in imminent danger of death or great bodily harm, and it appears that only an ordinary battery is what's intended, and all that is what the person fears, he has a right to stand his ground and repel such threatened assault, yet he has no right to repel a threatened assault with naked hands, by the use of a deadly weapon in a deadly manner, unless he believes, and has reasonable grounds to believe, that he is in imminent danger of death or great bodily harm.
See State v. Wanrow, 88 Wn.2d 221 (1977).
https://www.washingtongunlaw.com/stand-your-ground
I will be following this one. I think this situation is very simlar to the Ahmaud Arbery case in all the wrong ways