Some time ago I was used cheap Chinese LAN8720 Ethernet PHY 10/100 module.
https://www.aliexpress.com/item/33037526970.htmlIt is cheap, very simple and provides 10/100 RMII interface. Works very good and stable, almost no heating. The advantage of this module is that it doesn't requires a lot of signal wires. You're needs just 7 wires to use PHY (+2 for GND and VCC) and 2 additional wires for MDIO bus to configure it's registers. It works from 3.3V power supply.
The only con is that it doesn't supports 1 gigabit speed, the max ethernet speed for LAN8720 is just 100 megabit.
Since I need high speed transfer, later I switched to QMTECH board with RTL8211EG, it needs much more signals than LAN8720, but allows to use 10/100/1000 M speed.
So, if 10/100 M ethernet speed is good enough for your needs, then that LAN8720 module will be the best choice. But try to find some FPGA starter kit board which already has ethernet PHY on the board, it will be much more convenient when you don't have extra wires and modules