X11 and SHA3 ( Keccak ) are not ASIC resistant at all, according to NIST (National Institute of Standards and Technology), if you want to become SHA3 candidate, you need to be able to create by ASIC. AND every algorithms in X11 used to be SHA3 candidate until Keccak win the competition and become SHA3.
Each algorithm in X11 may individually be non resistant but it is not the case when they are combined. X11 is a set of hash functions and SHA3 is a hash function, apples and oranges.