I think title says it all

. I have never owned an ebook reader and am planning to get one.
I have read several posts in the forums and i have a slight idea of what my needs may be, still i would like your help.
Having tried to read on my 6" smartphone, i believe i need a bigger screen for reading, it was annoying having to scroll every few seconds because of the small reading surface.
I read almost every night before sleeping, so a screen with light is a plus.
I mostly download content, so sideloading easily is a must.
I have read that android ebook readers have reduced battery time, i would prefer something that lasts longer since i forget to charge my devices quite often.
Easy to use software since i have never had such a device before.
Greek language support would be nice.
Good handling of pdfs, though not mandatory.
The devices i have considered, due to lack of offer in our market, are the Tolino Epos, Inkpad3 and Kobo Forma, and to a lesser extent due to the smaller screen the Aura H2O.
However i can consider every option as long as it can be bought within the EU from a trusted seller, most importantly for the warranty.
Any help is welcome

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