Sign in to the PS5 with the PS Plus account
Go to Settings
Select Users and Accounts
Select Other
Select Console Sharing and Offline Play
Turn Console Sharing and Offline Play On
Sign in on the other user’s account on the same PS5
Download and play PS Plus games from the shared console
Use the PS Plus benefits on that PS5 for all users on the console
Keep the PS Plus account active on that PS5 for sharing to work