The honest status: the Sheets add-on is built and in final review, and is not yet installable from the Google Workspace Marketplace. Here's how to get it first, and what works in Sheets today.
The Google Sheets add-on pulls the same live bank data as the Excel add-in (balances, categorized transactions, and the 13-week forecast) into your own Sheets tabs. It is currently in final review, which means you can't yet install it yourself from the Marketplace. We'd rather tell you that plainly than hand you an install button that doesn't work.
Email michael@treasuryflow.ai with the subject "Sheets early access". The moment the add-on clears review, early-access requests get set up first, by hand, in the order they arrive. Early access is part of the same $99/mo plan; there's nothing extra to buy.