We have discussed this many times in the Legal section of the forum and the conclusion is that the best thing to do would be to hire a professional specialized in these matters to advise you, as what you can do will depend on the legislation where you live.
It's not necessary to hire a professional because there's a chance you might get a problem after that. The professional might force you to give him huge fees and threat you if you not do it or they will try to manipulate and make you always follow their words.
Based on the @OP story, those ordinary citizen just need to split his Bitcoin into few wallets and only cash out from little to big, not sell in once time. Although the chainalysis can track all of his addresses, but most of the time bank don't bother to check it.