Hi @Gregzddm, thanks for sharing this! You're correct that the Google sheets integration does not have a built in action type to rename a sheet or spreadsheet. It would indeed be a feature request to add that action to the integration and create a raw REST resource and query, so I'll log it in internally for our team to consider for future product planning!
As a workaround, you can try setting up a REST API resource to hit the Google Sheets REST API. The specific endpoint you'll like want to hit in order to change the sheet name is this one. Also going to drop links to OAuth2 in their docs as well as our own docs on creating a Google OAuth2 client that you can use for reference when setting up authentication for that resource.
Let me know if you run into any issues and we can help work through them