Fine i checked some things: My Firmware is still the outdated 9.X version with which i have generated Pokemon before.
The Pokeedit QR Code site is still working for me but a lot more annoying to save the edited Pokemon to Qr this again when you just change some little things.
Internet cache and the another things has been cleared.
So i think the communication error without crash or injecting has to do something with PkHeX.