The most powerful states don't need to launder any money, since they can just pass a law legitimizing any action they do, with no need to hide the funds generated from any one else.
This is irrelevant. Anything putin gang does is legal in Russia obviously but being able to clean blood money is vital for them. That's the point of sanctions and why any way around it like crypto is a godsend to dictators.
You're missing my point. Your example doesn't contradict it.
My point is that the most powerful countries don't need to clean their dirty money to spend their money abroad, because they are the center of the world economy, and everything is available to them to buy. Russia is economically on the periphery and thus does need to clean it.
Making it looks like "powerful country can do shady stuff and poor country needs to clean money" is not how reality works. Try being a violent dictator and do crime at a scale acceptable in Russia but in the US and then tell me how it goes.