AIUI, Kobo devices have a more advanced rendering engine if you name the file with .kepub.epub. (I think it's based on ePub 3?) Not sure if it would fix the problem here. But I personally run ePubs through kepubify (https://pgaskin.net/kepubify/try/) before transferring them to my Kobo.

Yes, I do that for everything too. Also publishers like Standard ebooks provide a kepub download - as they explain here they have problems with the Adobe reader too. https://standardebooks.org/help/how-to-use-our-ebooks#kobo-f...

I love my Kobo (clara colour) and really, if they just removed the Adobe reader, it'd be perfect. And yes, I've tried KOreader, but never switched to it because I like my Overdrive library books and Kobo Store.