Currently NiSi only makes one E-mount lens, the NiSi 15mm f/4 Sunstar ASPH (here at Amazon). By end of September NiSi will announce a new E-mount lens. I don’t know the exact specs yet but here are the images I got:
Nisi has launched a teaser action on their website and on their Facebook group. You have the chance to win this new lens for free.