Atlas Air, which some pilots have compared to a regional, does this.

Sometimes there are 2, 3 or even 4 captains flying together. Or 2 capts/2 FOs, 3 Capts/1 FO. Usually it is just 1 Capt, the rest FOs. Everybody is right (and left) seat quald. The FOs can't sit in the Capt seat during TO/Landing. Unfortunately, the FOs don't get "Cruise Capt" pay when they are the PIC/Left seat during the flight.