According to Bryan Alvarez of Wrestling Observer Radio, the current plan in WWE, as of yesterday, is to have Shane McMahon vs The Undertaker inside Hell in a Cell main event WrestleMania 32.
These plans can always change between now and the PPV on Sunday, and while there has been a lot of back-and-forth in WWE as to which match should headline WrestleMania, Shane vs ‘Taker is the current main event.