Both are knight-themed tokusatsu series producted by Toei. While they don't share the exact same class of knigths (King-Ohger goes more to the royalty side), they have the sabe vibe with the sword fights and the use of their respective swords to transform.

Both are knight-themed series in the Super Sentai franchise (although King-Ohger is more into the side of royalty). They are also directed by Kazuya Kamihoriuchi.

Crossover Kamen Rider films between the current season at the time this movie was released and the previous one. Both deals with time travel and feature an exclusive Rider that's an homage to Showa Riders.

Both tokusatsu show revolve around the villains trying to get a kind of energy from a source (the Enetron for Go-Busters and Victorium for Ginga S) in order to power up the big bad of their respective series. A special defense team is set to combat these threats.

Kamen Rider movies that take place in the near future where enemies have taken over the Earth and the main characters are part of a resistance group that faces them. The protagonists were thought to be dead, but suddenly return after a long time.

Tokusatsu crossover metafilms that celebrate a milestone in Toei's franchises. Heisei Generations FOREVER commemorate the Heisei Era Kamen Rider while Superhero Senki both Kamen Rider 50th Anniversary and Super Sentai 45th Anniversary. These movies know theirselfs as a work of fiction and interact with the "real world".

Both are a Sentai team that uses elemental/magic power. There's another world that provide their powers (Magitopia/Gosei World). The Goseiger team isn't made by a family of heroes like Magiranger, but two of them are siblings. The two of them also have non-human sixth rangers (although MagiShine has a human form).

Both consists in a Kamen Rider spin-off web series that are connected not only with the current series at the time (Drive and Zi-O), but also with some prior shows of the franchise. They are like some sort of a sequel for the previous ones: Kamen Rider 4 for Faiz/555 and Rider Time for Ryuki.

Boukenger and Gokaiger celebrate the anniversary of the Super Sentai franchise. Their plots revolve around an adventure to search for valuable things: the Precious for Boukengers and the Greater Powers for Goukaigers.

Super Hero Taisen GP and Let's Go Kamen Riders are crossover movies written by the same screenwriter (Shoji Yonemura) and take place in an alternate reality where the Earth is ruled by Shocker (the evil organization from the original Kamen Rider series).

Both are Kamen Rider movies that feature a crossover between the Showa Era Riders and the mostly current Heisei Era Riders at the time the film was released.

Both movies commemorate the Kamen Rider franchise, featuring a crossover between various Kamen Riders from Showa and Heisei Era.