Make All Form Settings Adjustable Per Business Unit
All form settings (Styles, Submission Settings, Non-HubSpot Forms) should be set up per business unit. Meaning that business units should NOT share these settings.
The whole point of business units is that you have different brands, different domains, and different go-to-markets.
I work for a parent company that supports multiple brands, and the forms settings in each section mentioned above need to be VERY different for each busniess unit because their business needs and use-cases are so different.