Which state is the most difficult to take any exam is it Massachusetts or New York

You seem to have a fundamental misunderstanding about how becoming a lawyer, doctor, or teacher works in the United States.

For the law, you complete college, take the LSAT during either your last or second to last year, and then (usually - there are exceptions but they are rare and most states don't do this) attend law school for three or four years and then take the Bar Examination. The Bar is two or three days long. The multistate portion accounts for one of those days and it is identical in most (all? Not sure about Louisiana) states. The state-specific portion is not necessarily easier or harder; it's more that what is considered a passing grade (on the curve) changes from year to year.

For medicine, you attend college (usually in a pre-med program), take the GMAT during either your last or second to last year, and then attend medical school and then intern and work as a resident. The GMAT is identical throughout the country. Any other exams you take in college are 'easier' or 'harder' depending upon your aptitude, the course work, the professor, etc.

For teaching, requirements differ among the states. Many teachers get a Master's degree and that requires the GRE - another exam that is identical from state to state. But you don't necessarily need a Master's in order to teach.

So the answer is that your question doesn't have an answer, not the way it's worded.

Agreed with you