Apart from the dude who points you to where it is, is the elder scroll needed because I sold it to the librarian at the college?

You sold your elder scroll ? No it isn't needed.

Good yeah for some stupid reason it came up for me to sell it when talking to the Mage librarian and I only got 2000 for it

Well you have to read it on top of the throat of the world. If you've already done that then no you don't need it any more.

there is a side quest you needed it for hermaeus mora.