I’m not an expert!
I don’t think there’s any way to ‘detect’ a Message has been sent as a filter on something else… Curious as to your use-case and reason why you can’t/want to avoid duplicating the Send Message filters in the Send a Card?
My assumption is your filters are numerous and/or very complex, and you’re doing this multiple times so doubling the quantity of filters you’re writing would be too time consuming?
My first thought (and something I’ve done a few times in my Flows for various reasons) is you can put the long/complex filters you require on a Set an Attribute action. Then anything else you want to be triggered by those filters just needs to check on the status of that Attribute with its Filter. You could have any number of Messages & Cards and all of their Filters would only need to be one thing; is the relevant Attribute ‘on’.
Hope that makes sense?