The White Sox start 3 Garcia’s in the outfield, first time 3 OF starters have had the same name, I don’t know about 3 starters at any position, I assume that must have happened or they wouldn’t distinguish.
The Alous played in the same game before but all 3 never started the same game.
In 1973, future Astros star Jose Cruz and his brothers Cirilo (Tommy) and Hector (Heity) all played for the Cardinals, and all played at least one game in the OF, but they never played in the same OF (much less all three start the same game).
I have to assume that three Johnsons or Davises or Rodriguezes have started in the same game at some point.