I have two forms on one page, how can I make both switch to the 'success' message when either is submitted?

As I mentioned, I have two signup forms on a landing page, one in the hero section, another further down the page. Both do essentially the same thing.

How can I make it so that both forms switch to their success message when either is submitted?

Hey Kelly- some guidance and throughts-

Thank you for the detailed response. Lots of good alternatives to consider.