WWE has announced that Stone Cold Steve Austin will respond to Kevin Owens today at 12 pm eastern. It's pretty obvious that Austin will accept.
Last night on Raw, Owens invited Austin to appear on The Kevin Owens Show at WrestleMania. His wording made it clear that, as of now, there are no plans for Austin to have an actual match but it's pretty obvious that KO will be taking the Stone Cold Stunner.
Here is the tweet about Austin from WWE: