The laws in Washington, U.S.A. are not pertinent to you unless you live there or choose to incorporate a company there. If neither then you aren't conducting business or creating taxable events inside the state.

Are you using a legal entity to hold the mining assets, or are the assets your personal property?  If it is just your personal property and you haven't formed a legal entity then taxation is determined by the laws where you reside.  Your mined coins could be treated as assets, income, capital gains, dividends, distributions, or any other categorization invented by the powers that be where you live.

If you formed a legal entity to hold the mining assets then taxation is determined by 1) the laws where the legal entity was incorporated, and 2) the laws where you live.  First, some places tax corporate earnings, dividends, capital gains, etc., and others don't. Second, the method by which you transfer assets from the legal entity to yourself could be a taxable event; it might be considered a dividend or salary depending on where you live.

To further complicate things, you could live in one country and have the legal entity in the other.  That's all sorts of fun.

The best thing you can do is talk to an accounting or tax professional to determine the most tax-efficient way to structure your operation.