Firstly, CBZ and CBR is a supported book type on all Kobo devices. You don't need to add anything to be able to read them. I don't read manga or comics, so I can't really comment, but, whenever I have tried one, they seem to work well.
For what you want, you need an Android device that will allow loading apps. I don't know an Android device with buttons. Kobo uses Linux and a native app, so they cannot do it unless you find a way to install Android. Someone has created
The UltimateMangaReader for Kobo devices. Maybe that is suitable.
And as you have a tolino, there is the tolino epos. That is a larger e-ink device. It is Android based. I don't know if there is a jailbreak to allow you to install other apps. But it doesn't have buttons.