box and cox

verb2

1. •
   (UK) To alternate with each other, often in the same post or location.

   • If any single production staked his claim to greatness it was John Barton’s 1973 RSC production of Richard II, in which Pasco and Ian Richardson boxed and coxed the roles of the King and Bolingbroke. — 2014
2. •
   (UK) To alternate between two people.