PlayStation confirmed the leaks that
Trophies will be available in both PS4 and PS5 versions of Monster Hunter Rise. The PlayStation Blog noted that PlayStation players do not need to be on the same platform to engage in co-op. A PS4 player can play with a PS5 player, and vice versa. However, it does not appear as if you will be able to take part in multiplayer with a player on a completely different console. For instance, a PS4 player would not be able to co-op with someone on the Nintendo Switch.
As for the general performance and mechanics of the game, PS5 players will have an advantage. For starters, PS5 players will be able to choose if they want to play the game in 4K (up to 60 FPS) or 1080p (up to 120 FPS). This option, as well as 3D audio, will be available at launch. There will also be additional feedback from the controller if you use a shield or Gunner weapons. This is due to the adaptive triggers in the PS5 DualSense controller.
Monster Hunter Rise will launch digitally for the PS4 and PS5 on January 20, 2023. Those who pre-order the game can get Layered Armor for your Palamute or Palico, as well as a Novice Talisman. It will also appear on the Xbox Game Pass. Monster Hunter Rise is readily available on the Nintendo Switch and Windows PC.