There are quite a few teams in the top two leagues that don’t really have a proper rivalry.
Reading, Hull, Stoke, Bournemouth, Huddersfield, West Brom, Watford just off the top of my head.
I’m sure they all have a team that they consider a rival, but cant say I’ve ever thought ‘oooh Stoke v Port Vale is a harsh rivalry’ for example.
Who is Leicester’s? Coventry? Cant say I really ever take notice of that as a rivalry either.