Well, actually the distanse is a problem for Ao Kiji, since it's better to BB to fight like that since he has Quake Quake Fruit to make damn strong earthquakes.

The only option for Ao Kiji is to speedblitz Teach in the begining of the fight and perform Ice Age on him and then pierce him with his ice spear enough times for BB to die.
once again, your overstimating his ability, BlackBeard cannot be as strong with the quake quake fruit like Whitebeard...why? simple, experience.
Basically, Some people, whom train incessantely, still do not achieve full potential of their devil fruits, BlackBeard, has 2 to deal with, so neither will come to their full potential, on top of that, blackbeard clearly puts the yami yami no mi, above, so he would rather use that, and will train more with that then the quake quake fruit.
Furthermore, If you check during the manga, no ability, is constant, that means, that before he can re-use the quake quake fruit he would have to wait, about 10 seconds if not more. For a logia, it's not so, they can keep releasing constantly their devil fruit, the fact that Aokiji is a marine admiral, and has only 1 devil fruit, should put him above both devil fruits, singularly. With some strategy, aokiji, stomps, just check Punk Hazard, just check the range, of their power, Aokiji, can ice age, the whole surface, making unfavourable for Blackbeard, and favourable for himself. Aokiji was also a marine admiral, his battle ability, is miles above that of blackbeard, he will not just rush into battle, he will take his distance analize, and take down his opponent. if he just makes a sword, that is enough, and we haven't even considered haki, Aokiji can just charge, and punch blackbeard with an armament haki punch.
There is no scenario, where blackbeard wins.