In runtime you can move data from one array to another, by copying from cell to cell - "Array2 Set value at (X,Y) to Array1.at(X,Y)". Do this in a loop, if you need to copy the entire row or column.
But it is not possible to modify JSON files in the project, so you will not be able to save modified arrays in the same JSON files. You can write them to Local Storage or some cloud storage.