Not sure if this is posted before but yea
If you want to share downloads with friends or your selling gameshes and you don't want them to sign in with your account every time to use it, you have to make their PS4 the primary system for your account. If you don't know how to do this, follow these steps:
1. Login with your account on your family/friend's PS4
2. Go to the "Settings" tab
3. Go to "PSN"
4. Click on "Activate as Your Primary PS4"
5. Click "Activate"
Now they should be able to use your downloads on their PS4. They don't have to login to your account to play your games or use your PS Plus and you could do this vice versa. You can still use your downloads without being primary if your signed into the account that has the downloads
heres a video (not mine)