Don’t bother focusing on collectibles, most of them you can’t get during the story anyway because they require skills unlocked later in the game. There are over 300 collectibles, but they are fast to collect and have a decent tracker on the map. In total you are looking at roughly 12-14 hours for the story and around 20 hours for the mop-up. You can jump between easy, normal, and hard at any time via the options menu.
There aren’t any difficulty-related trophies either. So just enjoy the game and play it how you want, mop up all remaining trophies afterward. You can get everything after the story in free-roam. None of the trophies / collectibles are missable. Even if you never played God of War it will be easy to understand. Welcome to the God of War 2018 Trophy Guide! This game marks a new beginning to the God of War franchise, with a completely new storyline.