To answer the question which was actually asked: No, you do not have to have a line check in *each* type aircraft, just in one of them. However, PIC qualification in more than one type is relatively uncommon in the 121 world.
§121.440 Line checks.
(a) No certificate holder may use any person nor may any person serve as pilot in command of an airplane unless, within the preceding 12 calendar months, that
person has passed a line check in which he satisfactorily performs the duties and responsibilities of a pilot in command in one of the types of airplanes he is to fly.