alt Hacker NewsLiquid handling in microgravity has always been weird. Big gas bubbles in the fluid, surface tension effects causing liquid to float in balls in the ullage, stuff like that. Turbopumps break if they ingest a larger bubble.
There could be some odd failure modes I would think. Failure to pump the liquid, broken pumps, who really knows? My guess would be that a failure mode would be a big spill, a failure to pump, only partially refilling, or broken turbopumps before an explosion.
For something like a transfer between Starships you can resolve a lot of those problems by (very) gently spinning the 2 craft. It won't take much force for the liquids to settle at the bottom of their respective tanks where you would presumably put the intakes.