So What would have happened if major league baseball franchises had never moved?

Here’s a stab.

NL East AL East
New York Giants Philadelphia A’s
Brooklyn Dodgers Washington Senators
Philadelphia Phillies New York Yankees
Miami Marlins Boston Red Sox
Boston Braves Toronto Blue Jays
   
NL Central AL Central
St. Louis Cardinals Chicago White Sox
Chicago Cubs Cleveland Indians
Cincinnati Reds Detroit Tigers
Houston Astros St. Louis Browns
Pittsburgh Pirates Atlanta Crackers
Montreal Expos  
   
NL West AL West
San Diego Padres Seattle Pilots
Denver Rockies Texas Rangers
Phoenix Diamondbacks Los Angeles Stars
San Francisco Seals Oakland Oaks
Los Angeles Angels