What do you call a movie with the same name in the same franchise, but not a direct sequel and set in a different universe or timeline? Like there are movies that are numbered, but where the second or third one feature different characters and who have no relation to the characters of the previous movie. What do you call these types of sequels?
When a series of films has some common thematic element, but doesn't share a plot line, you can call it an "anthology series".
John Carpenter and Debra Hill believed that the Halloween series had the potential to be an anthology series of films that centered around the night of Halloween, with each sequel containing its own characters, setting, and storyline. (wikipedia)
Individual movies in an anthology series are sometimes called (jokingly) "equals" (by analogy with sequel and prequel)