$Array2D = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9, 10]
];
$clonedArray = array_map('array_slice', $Array2D, array_fill(0, count($Array2D), 0));
print_r($clonedArray);
/*
run:
Array
(
[0] => Array
(
[0] => 1
[1] => 2
[2] => 3
)
[1] => Array
(
[0] => 4
[1] => 5
[2] => 6
)
[2] => Array
(
[0] => 7
[1] => 8
[2] => 9
[3] => 10
)
)
*/