B2 visa = tourism or family visit.
The only way you could earn money legally is to get a H1 visa or come as a temporary work force (can't remember the visa name).
What you could do is:
- employed by foreign company
- visit US for MEETINGS with colleagues at a US firm - come up with an agenda (of course you can code during your month here)
- your work cannot be directly FOR a US firm
- the US firm cannot pay you a wage/salary
- the US firm can reimburse your foreign employer for travel/accommodation to/from/in the US, who in turn would presumably cover your expenses while here.
The operative word is "meeting" as opposed to sitting in a cubicle and cranking out code.
What I outlined above is a very common occurrence. Many companies have foreign staff (or staff from foreign associated companies / partners) come in for business meetings.
*edit: i don't know if anyone else is reading this thread, but references for a trustworthy lawyer who can discuss a specific situation via email would be welcome.
But you couldn't get paid by a US office - it would have to be your Argentinian employer paying you and in their interest to have you here for business meetings (of course the US office could reimburse the foreign office for expenses, but now your salary) - that effectively means you will need to interact with a US office of the company you work for in Argentina (or an associated firm, e.g. in the case of the Big Four).
If you come for "business meetings" you should be ready to demonstrate such.