I know that Mickey Rooney played the Andy Hardy character numerous times. I think that there a couple of dozen Dagwood and Blondie movies from the 1930’s with the same actors.
The cast from the Harry Potter movies played the same roles 8 times.
The Fast and Furious actors are up to 7.
Robert Downey Jr. has played Tony Stark probably close to that. Samuel Jackson has played Nick Fury numerous times. As well as Hugh Jackman played the Wolverine numerous times.
Kevin Smith’s “View Askewniverse” movies have some recurring characters, including Smith as Silent Bob and Jason Mewes as Jay. They are about to make Mallrats 2 and Clerks III, which will bring the total to 8 movies, I think.