who is the new admiral that take sakazuki and kuzan place ?

Can't be sure at this point. What we do know is that there are two of them, and that there are a lot of possible choices. Akainu mentioned someone named Fujitora whom he trusts to deal with both Luffy and Law, so we can assume he's high in the strata. There are always the older possibilities among the vice admirals such as Tsuru, the great tactician, and there might be an up jumped character hoặc two from lower ranks like Captain Hina, but I doubt it for her at least.

its hard to predicts the new admiral...as we all know akainu will choose the true justices and strong enough to scared below yonko level...still before time skip there are non vice admiral that shown can compared the admiral...