When I was at photokina 2018, I stopped at the Kipon booth, and checked out the Kipon EF-FX 0.7x focal reducer (the quivalent of Metabones’ Speedbooster). Since I couldn’t test it, all I can say it that it feels very well build.
If you want to know more about it, definitely check out the Kipon Baveyes EF-FX ”Speedbooster” review at Mattias Burling Youtube.
PROS
all metal very sturdy build
USB port for firmware
similar results to Viltrox and Metabones focal reducers, and no so buggy like the Viltrox
AF for stills is pretty good
CONS
with some lenses swirly bokeh (the reviewers likes it, but some others might not like it)
X-H1 IBIS sometimes gives vignetting and ND sometimes creeps into frame
AF is not as reliable as native lens
not for streets and sports photography
Video AF is not great
You can purchase the following Kipon Adapters for Fujifilm:
“This product is the 2nd generation adapter for mounting Canon FD mount lens on FUJIFILM X cameras. It is equipped with 4 groups of 4 focal reducer lenses that reduces the focal length to 0.726 times in the adapter, even with cameras adopting the APS-C size image pickup device, it is possible to shoot with the original full frame angle of view of the lens.”