You would have to get the Big 10 on board for that to happen, and that's hard for me to see happening. They won't even go to the conference championship game format, so it's hard to see them participating in any kind of super-conference play-in format.
(And the reason they won't go to the conference championship format, of course, is because they can't. Do you put OSU and Michigan in opposite divisions? If so, most years the CG is just going to be a rematch of the only really big regular season game the B10 has. A conference championship game would expose the B10 as the top-heavy, big-two-and-mediocre-eight league that it is.)