To be fair, the ship did have 2 different weapon hard points on the model.I recall in the premiere Discovery 2-parter, them alternating between "phasers" and "phase canons" when describing the Shenzhou's weaponry.
There were the Connie refit style phasers which you see on all the DSC/SNW ships, and the phaser cannons that popped out of those hatches.
It probably wasn't the writers intent, but you can rationalize it that way

Best shot I can find right now.
Bit clearer on the STO model
