Is there any way I can find who edited a Google Sheet anonymously?
I have shared a Google Sheet with a group of users using a link but it was edited by an anonymous user.
I want to know is there any way I can get the IP address or any other detail of the anonymous user based on time they edited it?
That is not possible. Being able to edit something anonymously means others won't know who you are. If Google disclosed the IP of a user to a 3rd party (without a subpoena or such), that would be a privacy violation on Google's part.
The most you can do now is to undo any damage using revision history.
If you want to know who edits your shared files, don't share them as "Anyone with a link can edit". Share them with specific people: