We have the Virginia Project for work on Virginia profiles (pre or post 1700), please join us if you have an interest in Virginia:
Read more on our page for sourcing Virginia profiles here (in particular, see the note about state abbreviations not being used on Wikitree):
In particular, you can see the listed birth county resources:
However, if Elizabeth Mathews was born in 1685 then it would be impossible for her to have been born in King and Queen county as that county was not formed until 1691. Also, I believe Wise county (death location) was not formed until sometime after 1776, so also impossible. Perhaps Elizabeth was born in New Kent county in what later became King and Queen county?
Your proposed source, a profile on geni.com, is not a source in and of itself, but it may contain hints to help you find sources. Read more in the above link on sourcing for Virginia.
You need not contact us again for pre-1700 Virginia profiles unless you have questions or need help.
I'm happy to provide assistance as you may request in the future for Virginia, as this is my area of some expertise. I'm also pretty knowledgeable about DNA if you have questions there too.