Aura ONE ET Bembo font problems with italics

Hi, I have a problem with ET Bembo, downloaded from here:

https://ctan.org/pkg/etbb

I copied ETbb-Regular.otf, ETbb-Italic.otf, ETbb-Bold.otf and ETbb-BoldItalic.otf in the "fonts" directory of my Kobo Aura One.

On kepubs, the font is rendered as follow:

https://imgur.com/a/koVR2l8

Apparently, Kobo uses the "Italic" variant as default, and generates also slanted italics.

On epubs instead Kobo renders this way:

https://imgur.com/a/AZ6R6up

the bold variant is ignored, the device generates a bold variant automatically.

I have similar problems with Heuristica, PT serif, Lingua Franca, Gelasio and more.

Could you help me please? Thanks