The Ethernet cards we are talking about here, i.e. those using drivers:
1) com.apple.DriverKit-AppleEthernetIXL
2) com.apple.DriverKit-AppleEthernetMLX5
available in Sonoma in the com.apple.iokit.IOSkywalkFamily package.
If we use the vanilla Sonoma system, these cards will work without any problems.
Running broadcam wifi cards like Fenvi T919 requires adding a blocking entry com.apple.iokit.IOSkywalkFamily from Sonoma:
https://elitemacx86.com/threads/how-to-fix-broadcom-wifi-on-macos-sonoma-and-later.1415/
--> "STEP 4: Block Required Kexts",
and loading IOSkywalkFamily from Ventura
--> "STEP 3: Add Required Kexts".
It causes that the ethernet cards we are talking about cannot load the correct drivers (maybe IOSkywalkFamily from Ventura does not contain them) and this additionally leads to a system crash after a few minutes. It is not possible for these ethernet cards and "modern" Broadcom cards (such as Fenvi T919, BCM94360NG, etc) to function simultaneously in the system. The only solution at this point, in my opinion, is to use legacy Wifi cards that do not require IOSkywalkFamily from Sonoma blocking, such as BCM4331 and BCM43224.