Savage Tokusatsu is a Savage Worlds supplement that converts the general system into something that might run Kamen Rider, Power Rangers, or Godzilla.
Or live action Sailor Moon.
It's 99 pages, solidly full of illustrations, and the layout feels a little bit dense but is still completely readable.
Rules-wise, a lot of new build options are presented to the players. You get a variety of potential frameworks depending on how you transform, each with solid mechanical differences, and you get the option to play as a kaiju if your group okays it.
Kaiju are practically a different game, and don't really interact socially with the PCs unless you're doing a My Neighbor Totoro sort of set-up, so it may be better to have them as secondary characters that you switch to during the really big fights, rather than an everyday member of the party.
Setting-wise, ST offers a quick overview of the genre and then spins out several possible styles of play, depending on how you like your tokusatsu. Some have to do with different genres and level of grittiness, but there's also a really neat optional set of rules for kaiju-as-villain games where the kaiju is treated like an impending natural disaster with its own prep clock and the players are effectively readying a tower defense for it.
From the GM end of things, there's a heap of resources here too. There's monsters, items, infrastructure, etc, but also a full sample campaign. The tone for the premade material is more goofy, less dark, but there are some dark beats as well, and the campaign itself is a nice mix.
Overall, if you're comfortable with Savage Worlds (or if you're willing to learn the engine, which is super easy,) and if you enjoy tokusatsu storytelling, this supplement offers a lot of premade material that brings those two interests together. Some assembly is required, as it takes a toolkit kind of approach, but at worst it's handy and at best it's a way to take a familiar system and get really fun mileage out of it. If you like Savage Worlds, and you like the media mentioned here, give this a shot.