Yes, pilots selecting "up" on the trim switch should stop and override MCAS. But it also "resets" MCAS so that it will pitch down again on its next cycle. So yo

Yes, pilots selecting "up" on the trim switch should stop and override MCAS. But it also "resets" MCAS so that it will pitch down again on its next cycle. So you'd have to be constantly correcting it, or switch the electric trim off entirely (i.e. treat it as runaway trim).