Yup the mini pcs are better than raspberry options. They have multiple USB 3.0 ports.
M.2 to ethernet adapters are sold in aliexpress like https://s.click.aliexpress.com/e/_oBpZQJG idk if driver is available. On these thread it says it was successful Does OpenWrtx86 support Realtek 2.5Gbps Nics? (RTL8125B) with r8169 driver.
Usb to ethernet adapter drivers are available.