They are already here. I have a group of Novoflex adapters for Leica M, Leica R and Nikon F. All manual focus of course. I also have a Novoflex AF adapter for my SL, which isn't actually very good. Now whether this will work on the Panasonic FFMC's who knows.But I doubt it. Sigma have already announced that they are making two adapters, one for SA > L Mount and one for Canon EF > L Mount. Hopefully this latter one will be better than the Novoflex. Sigma will of course specify that it's made for their EF mount lenses and they can't say whether Canon lenses will work. I guess the question is whether a company like Metabones think it's worth their while to offer AF adapters. There will certainly be some cheaper Chinese ones as they seem to make adapters for everything. With any luck some might surface before the Panasonic FFMC is on sale as somebody might think it's now worth making adapters for the SL, since it's going to be joined by other cameras in a few months time.
I really look forward to Sigma making a Nikon to SL adapter so I can use my very lonely Sigma 105mm f1.2 Art Lens on the SL.... I want to try a Novoflex but it is an expensive experiment if it does not work. I can sorta deal with slow AF but really want consistent aperture control. I use a manual Novoflex for my old Nikon D lenses. I just sold my D810, opting for pure Leica bodies but have kept my older manual aperture Nikon glass..
The Novoflex Nikon > SL adapter only works with lenses that have electromagnetic aperture control - The 'E' lenses. I understand some new Sigmas have this some don't. As I indicated above the Novoflex Canon EF > SL adapter is very slow for AF, even when it works. I use my lenses in MF most of the time, it's actually quicker.