I wonder how well the simulator engine (and the aircraft configuration files, and the Aircraft Editor in the SDK) handle delta-winged aircraft? What about elevons? Flaperons? Canards?
Yes, I know that especially for FSX there existed lots of add-on aircraft like that, but most likely they were not quite simulated properly, were they? Did the add-on developers just hack it until the aircraft behaved as expected, possibly even using a separate flight engine in their add-on, even if the simulator core as such might have thought that it is simulating an aircraft with conventional wing and control surfaces?
Does it answer your question ? simMarket: PAPERCRAFT AERO DESIGN - UL STRIDE MSFS
I dunno if you can import your own wing numbers / NACA profile now though, and maybe that ultralight is using a false wing…
I’m no mod nor dev, but I hope that helps a bit.
Does it answer your question
Not really, that page doesn’t tell any implementation details.
It shows still that “in some ways” it can be done. As implied, you’ll have to get in touch with this developer to know how he did it, or the dev community here to have the right answers, but at least you have a start of a clue 
It is not like you will get the answer from Ms / Asobo anyway !!!