Which country will agree not to tax you on your offshore account? I don't know any civilized country that would agree with your tax evasion.
Sure, sure.... as long as you stay under the radar.
I live in Germany and I don't pay taxes on my trading. I have a regular job and never told anybody, authorities included, about my financial career.
Also I spent a year in South East Asia and I could never imagine authorities asking me whether I pay taxes on my trading. They just care for the visa. And taxes from a regular job or a business within their country. But not profits from an "online business company", as is also trading.