1) You cannot define a field group only on a single admin page. If you do this the field group will not be usable anywhere but on the admin page. You will not be able to get the values of these fields anywhere other than on this admin because the field are only defined when loading this admin page.
2) You cannot add an ACF field group inside of one of the existing WC product data tabs. I say can’t, but it is possible to do this using acf_form() by inserting it inside of the existing form without form tags as long as you comply with #1.
