RTL8111/RTL8168 driver is not included by default and hard to install.
could vyos include it in future release?
there is a r8168-dkms debian package that may works well.
https://forum.vyos.io/t/how-to-install-rtl8111-driver/3511
https://www.unixblogger.com/how-to-get-your-realtek-rtl8111rtl8168-working-updated-guide/