As I understand it, PSN accounts - the ability to play online - are free, I know that everyone in my family has one and we're able to use them both individually and simultaneously. Multiple characters and all.
The paid account, PlayStation Plus, is tied to a user, but I have downloaded the "free" content using my PS+ account and my son is able to play those games.
EDIT: I haven't played Elder Scrolls, but we've played multiple online games using individual free PSN accounts.