Hyrule Warriors: Age of Calamity is a prequel to a sequel and a sequel to a spin-off. It's also really bloody good, I reckon.
With a more complex Warriors formula than usual, a diverse range of characters that have their own play styles as well as movesets, and a whole ton of content, it's mechanically superior to the first Hyrule Warriors, even if it doesn't quite benefit from the original's novelty factor.
Also, you get to keep all your weapons.