My knowledge of (1789) English is not enough to understand Section ii) of the Sixth Article:
This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.
This seems to impose US Constitution as the main regulation and the only standard for assessing any law in US. But is somewhat dogmatic. Who will decide and how in cases of conflict?
This could also mean that Federal Law imposes it’s rule over Particular States Laws or even Particular States’ Constitutions (Do these exist?). But there’s again the problem of assessing: Laws of Particular States could be “Laws” made “according” to the (US) Constitution and the Federal Law could be against it.
On the other hand, in the mention of Treaties made “under the Authority of the United States,” what does “Authority” mean? That International Affairs are just “Federal Stuff” (as in Spain, where Autonomous Communities are also prevented of having a say in Foreign Policies, or even relating with other countries)? I’m afraid that, as in Spain, according to the text, States’ Governors aren’t considered “Authorities” of the United States.