I would like to use a laptop with SunSDR2 DX (ver.5) that does not have a LAN port but has USB-C available. Are there any known problems with the USB-C / LAN adapter ? Which one is best to use ?

Majority of modern laptops have no in-build Ethernet port and use USB-C-to-LAN adapters. Mac laptops have no in-build LAN since 2016 and all use adapters (and we have more that 10 Mac users here).

The only known problem to such adapters is user himself (typically not reading/not following manuals), otherwise adapters are reliable enough to do the job.

I use a usb 3 to eathernet on two dell laptops. They work fine no issues.