I can concede it as even, though Corrin's side b can shut down the matchup as Ike cannot punish it. It just makes the matchup extremely difficult, even if you read and powershield it.
However, Corrin has virtually nothing at close range. IMO Ike should play this matchup defensively. Corrin will often try to fast fall her aerial combo starters (fair and nair), and if she misspaces or lands on shield, then Ike can grab/dtilt/bair/jab/pretty much anything. Also, ftilt puts Corrin in a horrific position offstage. It makes it easy to use counter on her recovery.
This matchup is by no means impossible, it's just difficult for Ike.