There is no way to update samsung software itself on s8 galaxy via ethernet to usb-c cable connection, only options are wifi and cellular data. There needs to be a third for ethernet. Doing so over connected ethernet gives an error of no network connection.
Are you talking about the OS software? Those are pushed by the service provider so could not be done vial USB.
Is this a developer related question it does not appear to be so and I will remove it in a few days. Let me know more if I misunderstood.
Ron
Samsung Developer Program
I always thought samusng updates are done by samsung, not your cell provider. But as you say. Whether you choose wifi, mobile data or ethernet to download them is up to you, and doing it over ethernet cord doesn’t work for some reason
The Samsung updates are done by Samsung they are distributed by the Service Providers because the provider usually have variations specific to their network.
I apologize if I confused you.
Ron
Samsung Developer Program