GeckoCovers has announced their first Kobo Aura ONE cover, in black It would be available in about three weeks.
It looks like this is going to be the standard Gecko cover that covers the bezels. I like that. On my Kindle cover, you slide the reader into the cover from the left, and then put a retaining flap over the edge, and under the reader, which is held down by velcro. In the past, I've seen Gecko covers that didn't have that flap, which made the reader prone sitting askew in the cover, or even slipping partly out of it. I hope they do have a flap like that nowadays.
edit: going by the (generic) product video, they still don't have retaining flaps. Also, thinking about it, my KPW1 cover is exactly the same as the Gecko one (but *with* retaining flap), and it only cost €12 instead of €27.
I'll probably wait and see.