Meaning of に in ～にできる

Question

In the sentence,

これまでの借金を全て帳消しに出来る…！！

What is に doing here ?

Answer 1

帳消し is a noun referring to "the state of being cancelled out/wiped clean", and its verbal form 帳消しする is not particularly common. The usual verbal expression for "to wipe the slate clean" is 帳消しにする, and 帳消しにできる is simply the potential equivalent.

In essence, this is the basic usage of XをYにする to mean "to make X Y", which itself is essentially a transitive equivalent of XがYになる "X becomes Y". So for instance:

ドラえもんが次の大統領になる。
Doraemon will become the next President.

ドラえもんを次の大統領にする。
I will make Doraemon the next President.

ドラえもんを次の大統領にできる。
I can make Doraemon the next President.

帳消し follows the same basic pattern, with 帳消し as the indirect object Y:

借金が帳消しになる。
The debts will be wiped clean.

借金を帳消しにする。
I will wipe the debts clean.

借金を帳消しにできる。
I can wipe the debts clean.