You can play the single player experience in full and receive Steam or Epic Games Store achievements, without signing into a PlayStation Network account.
Signing into a PlayStation Network account is required for Legends multiplayer mode and for use of PlayStation overlay, including PlayStation Trophy support.
You can also link your Steam account with your account for PlayStation Network to gain early unlocks. This is optional.
How do I create and/or sign into a PlayStation Network account?
When starting Legends mode from the main menu, the game will show a pop-up asking you to sign in to your PlayStation Network account. If you do not have an account, you can create one by pressing the “Create an Account” button. Alternatively, you can create an account on the PlayStation website.
I need help with my PlayStation Network account
For any support requests related to PlayStation Network accounts and account linking, please reach out to PlayStation Support.