Maybe I don’t know all the functionality in online excel, but I feel like google sheets offers a great online spreadsheet experience.  As far as related to audit, you can set up variables so as people complete things it notifies you (either at the time and/or in a daily summary) and provides an audit trail of changes to the cells (which is a great feature), and being able to go to prior online versions of the same file, so if you made changes you don’t like and there’s a point you did like, you can go directly to that time and restore from there.  So many great features above and beyond a desktop spreadsheet.

I never use Excel online, I just find that I am faster and more efficient while working in the app.

If in doubt - ask AI...

Excel Online is a streamlined version of Excel for the web that's designed for basic spreadsheet tasks. Excel Desktop has more advanced features, including macros, Power Pivot, and Power Query. Excel Desktop can also be used offline, while Excel Online requires an internet connection. 

Features:

Advanced features

Excel Desktop has more advanced features, like macros, Power Pivot, and Power Query. 

Offline access

Excel Desktop can be used without an internet connection, while Excel Online requires an internet connection. 

Collaboration

Excel Online allows multiple people to work on a spreadsheet at the same time. 

Review menu

Excel Online is missing the inking editing, language translation, and embedded thesaurus options. 

View menu

Excel Online is missing the page break, page layout, custom views, zoom options, and formula bar hiding options. 

Use cases: 

Basic spreadsheet tasks

Excel Online is designed for users who primarily work with basic spreadsheet functions.

Complex data analysis or automation

Excel Desktop may be more suitable for users who need to perform complex data analysis or automation.