Cannot find a python solution for n = 8. So I tried to check the result

n, palindrome product, x, y

2 9009 99 91

3 906609 993 913

4 99000099 9999 9901

5 9966006699 99979 99681

6 999000000999 999999 999001

7 99956644665999 9998017 9997647

8 9999000000009999 99999999 99990001

When n is Odd, the result is always 9* 9 (n 9s) * 990**1 (n/2 9s with 1 )

No sure whether it can be extend to odd n > 8 (but for any Odd num, it seems that at least the product of such two numbers is a palindrome, not sure whether it will always be the max)