I use MBP with Catalina 10.15.3, ADE 4.5.11, Tolino Vision 3HD (disigned by Kobo, I think) with firmware 13.2.1.
Downloading and reading eBooks from public library with ADE is perfect. Everytime I connect the reader with the MacBook it lasts 3 or 4 seconds and ADE crashes. So transfer of eBooks to the reader is impossible.
Would be happy to get help, because the so called "onleihe" (means public library via internet to load epub-files) is not able to communicate with the producers of Tolino to realize direct downloading from the library.