Here's a highly hypothetical (though I do personally hope for it to happen) take:
Well, as long as the J-35 is fully ready for at-sea carrier-based trials - I believe that conducting the first ever landing trial with a J-35 on Shandong while at sea is definitely worth it.
This is especially true if China can use the occasion to "slap" US Secretary of State Antony Blinken's face right during his visit to China in the coming days - Just like how China "slapped" the face of ex-US Secretary of Defense Robert Gates back in January 2011 with the first flight of the J-20 conducted just a day after his arrival in Beijing XD
Well ... if the J-35 is already that far progressed in its flight testing is one question (which I think it is not yet) besides if it is capable to do so in principle (which I think it is); however I don't think the PLAN and SAC will risk this only for a PR stunt.