If you are talking about merits (and assume that you have minuet on), AF+1 will yield better averages than ochiudo or af2 for jin.
ochiudo:
At merit levels, the +atk items diminish in value, since it's usually boosted significantly by your brd or cor.
af2:
Upon cursory glance, you might think from the WS modifier that 6str+6dex is not as good as the +12 str--after all, str has the side effect of modifying effective dmg. But, Jin's higher end damage is entirely dependent on the criticals occurring. You want to increase the chance of it happening as much as possible once you have procured the baseline acc and atk. Criticals go up roughly 3%/10dex. With a low weapon-rank weapon like a katana, the +12 str from AF2 doesn't add as much to your average.
Of course, if you are not talking about merit mobs, the story changes. For stuff with really high def or eva, boosting atk/acc usually yields better results than boosting any stat.