This could take some work that I might have to pay for, but your website said to contact you with things other than support. Not sure, so posting here first.
Basically my question is the title. Could the plugin modify WordPress itself to return a search page with all terms from all taxonomies matching the hashtag?
I'm broke for the next two weeks, but I'd sponsor this with what I can to see it as an add-on plugin or available option in the plugin itself. It would make my dreams come true, and there may be others out there who'll appreciate it.