I want to view my list as datasheet. But I can't see it anywhere. Some sources that I found in Google said that I need to open in IE. But there's still no DataSheet option
Quick Edit will open a spreadsheet view of your list online. Export to Excel requires desktop Excel and will download the data to a local Excel file.
What you may also be interested in is to create a datasheet view: Ribbon>List>Create view>Datasheet view:
I have a client who has had this same problem in SharePoint Online/O365. Verified that content approval wasn't turned on, point of contact user's browser updated, quick edit feature enabled, etc. Quick Edit view would allow editing in what we know as datasheet view, and two days ago, the Datasheet view based on the datasheet view option was functional.
My solution: create a new view, based on Datasheet option, same column settings and view order. The new Datasheet View works as expected, so deleted the previous one - but their settings and configuration was identical. Since this client has no browser requirements defined (users can use whatever version of whichever browser they prefer), so running down browser settings was not viable.
I'm following along to see if there is a cause that might be flagged down the line.