New Hire Training
 

I’ve heard that all new hire FO training maneuvers are done in the left seat for the cargo carriers, as opposed to the right seat with the majors. Is this universally true for all the supplemental?

Universally BS :D Not true

That used to be true at Atlas. New hires had to do all their training and type ride from the left seat. But it changed about 5 years ago, or so. Now you train for the seat that you sit in.

No. There are certain things you need to do from the left seat, namely taxiing and an aborted takeoff, for the type rating checkride. Other than that, at least for my employer, it's all right seat.

Atlas FO Training
 

At Atlas, the PF maneuvers are all from your assigned seat, eventhough you are getting a PIC Type Rating. The 767 taxis only from the Left seat, so the high speed reject and 2x 90 degree turns are from the left.

However, if two FOs are paired together in training, they will need to be familiar with the CA flows and procedures inorder to get off the gate in training. On the type ride, seat support will cover all the CA flows and calls.