Just read this thread from the beginning page 1 and it explains how!Thank You for asking this question! I've always been really interested in the possibility of adding national teams and extra club teams but I can never quite get it to work. I'm mostly interested in career mode so I originally tried to replace the extra FUT teams IDs - to no avail. It seems like there are a few ways to replace existing teams though. Hopefully someone smarter than I can put together some instructions eventually to simplify the process!