The Bill of Rights is a charter adopted by the States at ratification, it has ALWAYS applied to the States. Read for example the wording of the 6th. That additional protection of citizen rights in jury trials applies to all jurisdictions, not just Federal.
The same philosophic forces that would not join a Union that banned slavery quickly re-interpreted the Bill of Rights as “un-incorporated”. That is, judicial fiat.
Incorrect. They weren't adopted until the First Congress.