The shortcode supports a text attribute e.g.
[lh_qr_code text="Pete can program"]
see example here : https://shawfactor.com/2016/06/13/qr-code-test/
I’ll add documenation for this feature in the my next relase this week
In terms of a form to automatically create a post, obviously the plugin doesn’t support that natively but i could build it easily enough if you wanted to hire me (I’m very reasonably priced).