Open("C:\\Users\\Asukaze\\Documents\\a.csv");

b = Bottom;
r = Right;

data = {};
for (y = 1; y <= b; y++) {
  data[y] = {};
  for (x = 1; x <= r; x++) {
    data[y][x] = [x,y];
  }
}

Open("C:\\Users\\Asukaze\\Documents\\b.csv");

InsertRow(1, b);

for (y = 1; y <= b; y++) {
  for (x = 1; x <= r; x++) {
    [x,y] = data[y][x];
  }
}