An anonymous source now send me the first image of a MK18-55mm T2.9 X-mount prototype mounted on the Fujifilm X-T2 (thanks a lot).
If you want to see, how Fujifilm’s MK lenses are manufactured (and also other X-mount lenses and cameras), feel free to check out this article about the Fujifilm factory tour.
UPDATE: Interview with Fujifilm Manager about the MK lenses. They talk about and show also the Fujifilm X-mount version. The manager says that the price can’t be very different from the E-mount version and that they try to come out with X-mount version within this year (2017). More at newsshooter (thanks to the FR-reader for sharing the link in the comments).