If you look at the law requiring an engineers license and the definition of "the practice of engineering" in WA
https://app.leg.wa.gov/RCW/default.aspx?cite=18.43.020 its a big broad paint brush.
The exemption in WA is probably like Oregon is where Master / Supervising Electricians can design work they build.
That is why the Master / Supervisor test in OR and WA are notoriously difficult, as your practically considered an EE.
So for example it would be illegal to draw the plan set for the sky scraper and send it out to bid.
But it would be legal for you to design / build the electrical.
There was a case here recently where a guy was discussing the timing of trafic lights in court and they cited him for practicing engineering without a license.
It happens in other states also:
A retired North Carolina engineer volunteered his professional opinion during a lawsuit, now the state says he’s in trouble for practicing engineering without a license.
www.vice.com