Netflix videos in hd watch with widevine l1?

Are there modded apks with which I can also watch fhd at Netflix with widevine Level 1?

The copy protection intervenes at the processor level. Therefore, you can forget that with a modded app.

Does not work, and does not exist.

But surely there's a way to hide the new kernel, and so on

Nope! Once you unlock the bootloader, it's all history!