This beautiful livery was designed by Textron Aviation to promote their aircraft on their official website: https://cessna.txtav.com/en/citation/longitude (bottom of the page)
You can enter the registration you want directly in-game.
Important : Aircraft model provided with Microsoft Flight Simulator 2020 Premium Deluxe Edition only.
I hope you will have as much fun flying with this livery I took to reproduce it.
Simply unzip Neuroflight_Longitude_Artwork.zip file and drop Asobo_Longitude_Factory_Art folder into your Community folder.