What is the ruling on the oath required for practicing the legal profession, with the intention of respecting only laws that are in accordance with Sharia, knowing that the country's laws include both man-made (positive) and Sharia provisions?

There is no harm in taking the oath required for practicing the legal profession, with the intention of respecting laws that conform to Sharia (definition). This is based on two proofs: First, an oath is judged by the intention of the one administering it, not the one taking it, in the case of swearing a false oath. Second, scholars have permitted a Ghamus oath (a deliberately false oath) for a good purpose, such as hiding a Muslim from an oppressor.