All motherboards use rj45 plug. I225-V is 2.5gbe speed, other common speeds is gigabit. Gigabit or 100MB/s, can be utilised with cat 5e or 6 cable. 2.5gbe requires a router and cat 6 for those speeds + appropriate internet connection and storage drives to handle transfer rates. Also negotiation speeds between gigabit hardware and 2.5gbe can sometimes be problematic. If your house uses normal gigabit lan environment, don't get a motherboard with I225-V. Someone can correct me of course but it's what I've experienced with a friend over for a lan session and they had to rely on wifi because god forbid they couldn't connect via lan cable.
A lot of boards have Intel ethernet, even AMD motherboards. Realtek offers many ethernet chipsets and are pretty common to see on motherboards. Marvell maybe sometimes, haven't seen one in a while.
Most other ethernet chips are found outside of the motherboard as discrete cards, components, routers, etc. Broadcom, TI, and Microchip and the like.