Can a person change a visitor visa to H1B visa without going through counselor processing outside the country?

An alien who has made entry into US under one non-immigrant visa may before the expiry of the period of stay change to another non-immigrant visa category, if so qualified. However, depending on the timing of such change, CIS may have concerns regarding your true intent when you entered in one visa category and then changed to another visa category. An H-1 b petition allows you to work under the terms of the H1b. However, you are permitted to work as an H1B non-immigrant work er only for the employer who filed the H1 b petition and then, only after the approval.

Depending upon the specifics, a change of status request may be an option to consider.

If he was not in the US when the H-1B was filed, then he was not in any status in the US so he cannot just come to the US and start working even if the petition is approved. He would have to go get a H-1B visa once the H-1B visa petition is approved and enter on that visa, thereby activating the H-1B status.

The H1b petition must be filed by the employer, not the employee. Only after it is approved, can you apply at the US Consulate.