I installed Apple macOS 11 Drivers Installer(Beta) version 1.0.0d3 from ASIX site and followed their Readme instructions.
The ethernet adaptor works fine.
My system specs: Big Sur 11.2.3 (20D91)
MacBook Pro (15-inch, 2018)
CSL - HUB USB 3.0 incl. Gigabit Ethernet with AX88179