Dang! I just love this little e-reader, its way faster than the pocketbook Inkpad3

. Its a shame that its the only current kobo model that allows for micro sd storage

.
Anyways, following the tutorials from
https://yingtongli.me/blog/2018/07/29/kobo-sd.html I was able to upgrade the puny Sandisk Edge 8Gb included from factory for a Samsung evo plus
512Gb [MB-MC512GAEU], in reading and writing about twice the speed (although its debatable if the host of the kobo can take advantage of it)

(and for sure A1, A2 new monikers for other high-end SDcards... yeah, almost certain that this device wont be able to take advantage of that, sadly...

)
It works, no problem at all, so I hope this helps for those interested
Side note: installing Koreader is worth the hastle (not in the pictures). Koreader FTW for having a file manager which is lacking in the kobo software, this feature is needed when having to deal with so many files