Ok, I purchased
https://www.amazon.ca/NetDot-Generat...+charger&psc=1
and
https://www.amazon.ca/Generation-3-3...9322382&sr=8-2
for all my kobo touch's and kobo Aura for my wife and daughters kobo.
The only issue I have is that it was a really tight fit, at first I thought it might be the wrong connector type and then I thought I was going to break it. At least I know the little adapter bit won't fall out of the kobo, I think you'll really have to yank it out to get it off (haven't tried - I'll do that when the time comes if need be) in any case tight fit.
The 3 silver magnetic cable connections charge and connect with data transfer with the light up (haven't tried the other way) says they're gen 3 and are compatable with the gen 5 adapters I also purchased.
If you want to be able to connect using the old cords you'll need the adapter piece from the first product I mentioned - that adapter piece doesn't come with the silver cords. Although just thinking now, I think I only needed the adapter because the one will mate with your old charging cord and the smaller piece will plug into your kobo - but i don't actually know if the cord will work with it or not. I only bought the silver cords because I thought they were only compatible through it. (updated - it does work with your usb kobo cord)
***added info***
Ok, tried the adapter in the old charging cord and it works good. One does have to make sure the light is up, if it is down (at least with the gen 5's) computer installs new hardware for device and then doesn't recognize it - so just make sure the light is up. No problems though just pull it off and flip it around, nothing happens to it by plugging it in the wrong way.
One other thing, the magnet is fairly strong, you have to pull it to disconnect it. One reviewer said if he just knocks the cord and it falls off - I would either think it was a defective one or maybe an earlier version that might have had a weaker magnetism - regardless I see no problems with the strength of the magnets.