Here's my take bro, maybe the SK companies may set up a subsidiaries inside China and use domestic equipment. ASML seems to smell the tea and are going that route by establishing a repair and maintenance plant in Beijing. They may rename it like from Samsung to Tristar Inc as an example. (Samsung is a Korean translation of 3 star).
How feasible is it? If the US enforces a total blockade on US related things with all the major countries involved in semiconductors via trade agreements. Then the subsidiaries will have to use 100% alternatives to remain compliant with the restrictions.
Except the government will prioritized domestic equipment for domestic Chinese companies. As they aren’t going to prop up South Korean companies when Chinese companies are more important. More likely scenario may be South Korea selling off all their Chinese fabs.