I think ESPN still has first dibs on most games, don't they?
EDIT: This article is a couple years old, but it says ESPN/ABC airs 27 Big Ten football games, with at least six of them being in prime time. Fox/FS1 airs 24-27, nine of which will be in prime time, plus the B1G Championship. Fox gets first pick most weeks, but ESPN has priority in some weeks.
https://awfulannouncing.com/ncaa/know-new-big-ten-rights-deal.html