With a little bit of rotating this plate fits 225x225 print platform. I printed this with Ender 3 Pro.

To make a full Hextraction board print one of these and two of Zack Freedmans 5-7 Plates (https://thangs.com/designer/ZackFreedman/3d-model/Hextraction%20Game%20Boards-856439).

I noticed that with this piece one could build a longer version of original base plate. The original size is 5-22. I currently have 5-32 base plate.