Both are capable 9.2 AVR with 11.2 pre-outs to complete 7.2.4 layout.. The Accu EQ on the Onkyo AVR is supposed to be an improved version over the previous Accu EQ calibration found in previous generation AVR.. It is said to apply EQ to only part of the freq range (<=500 Hz) and not completely..
Marantz SR 6013 on the other hand has Audyssey XT32 and has the capability to adjust EQ range thru apps if you would prefer that option..