Until Independence everyone in the Colonies were subjects of the crown and so
jus sanguinis did not apply.
That the framers meant to use a Vattel basis where the Natural born must be not only born on the soil but of jus sanquinis (born of citizen parents) is the inclusion of the out that they gave themselves to be President. They were mainly native born but they were born as English subjects.
So I do not think that this is an established fact. Just a hint you would do better to link me to some scholarly article and let me decide for myself. Or to case law if applicable.
Until Independence everyone in the Colonies were subjects of the crown and so jus sanguinis did not apply.
As subjects, the
jus soli principle applied to anyone born in the colonies, and the
jus sanguinis principle still applied to those born outside the realm of the British Crown.
As for links to information confirming the historical colonial and new state statutes and common law on the issue,
see, e.g.,
(a) The historical discussion
described by the Supreme Court as an "elaborately argued ... and decided upon full consideration" discussion of the history of colonial and early state citizenship law
in this case (beginning at p. 237), or, if you prefer more modern type, you can read the case
here (concluding that
jus soli determined US citizenship and stating further (in dicta, of course) based on the universal statutory and common law in effect at the time of the Constitution, that a child born to foreign parents would be a natural born citizen qualified to be President).
(b)
William Rawle's A View of the Constitution of the United States (pp. 85-86). Rawle has been cited frequently by the Supreme Court, including Scalia, who
quoted from Rawle extensively just last year, for purposes of understanding the original intent of the Constitution.
(c) While I'm not sure if you consider the National Review-published
The Heritage Guide to the Constitution, edited by Edwin Meese III, et al scholarly, it has a discussion about Presidential Eligibility and, more particularly, the "natural born citizen" requirement as well (pp. 189-91).