A Kou has the better feats, but Roku O Mi has the better stats.
ROM is overlooked and underestimated by a huge portion of the Kingdom fandom, in large part, I suspect, because of his personality and this particular audience having an affinity for edgelords and the cooler, more served characters they like to project themselves on, e.g. Kan Ki, Ou Sen, A Kou, etc.
Regardless of how he is perceived, though, Roku O Mi is a very powerful combatant, a highly capable leader, and an experienced veteran. Hara didn't give him these stats for nothing:
STR 92
LDR 90
INT 82
EXP A
A Kou's stats are:
STR 91
LDR 89
INT 87
EXP B
Granted, stats are inherently arbitrary and don't tell the whole picture. They certainly don't determine the outcome of any hypothetical scenario. The circumstances do.
imo, Hara's stats leave a lot to desire in terms of reflecting what's on the panel, and on that basis alone I would have given A Kou a 93 in STR and 90 in LDR - that's just based on his performance.
This is match is pretty close. I'm personally leaning towards ROM in a duel and towards A Kou in a battlefield scenario.
That said, while not as impressive, we did see Roku O Mi call out formations during the Coalition War, so perhaps we'll get an opportunity to see how deep that skillset goes for him at a later date.
That said:
Just, no. This is a highly a difficult win for whoever wins.
This is insulting to both Roku O Mi and A Kou.