[DiMaggio5CF]

You could do Northeast, MidAtlantic, North, South, Midwest, and California:

Northeast (4)
NY Yankees
NY Mets
Boston
Toronto

Mideast (4)
Philadelphia
Pittsburgh
Washington
Baltimore

North (6)
Seattle
Detroit
Cincinnati
Cleveland
Milwaukee
Minnesota

South (6)
Florida
Tampa Bay
Atlanta
Houston
Texas
Arizona

Midwest (5)
Colorado
Kansas City
St. Louis
Chicago Cubs
Chicago White Sox

California (5)
Oakland
San Diego
San Francisco
Anaheim
Los Angeles

If you're starting a custom league, this will do. But if you're shuffling an already existing league, you might have to switch one team from a 6 division to a 4 division to make it fit.

I think you can use "Create Division" and "Create Team" to make it fit, but it's a lot of work.

You can change the name of the Northeast Division to the New England Division. Only one team (Boston) is actually in New England, but it might make it sound better than having Northeast and North.