A small “Connector-on-Board” Plug-In Module with
W5500 chip + with 8pin 100mil distanced
Pin-Headers 'Breadboard friendly' Footprint. The W5500's SPI I/F and PHY
I/F is free available. The vertical RJ45 for Top side connection.
The W5500CoB Module is made by German company ESoPe.
Here pictures of Top and Bottom side:
The schematic is here:
The Pinout of the Module in detail is here:
In the WIZnet EU's Blog is a nice explanation about how to connect RJ45 and make a short test setup.