Pigs are *much* happier indoors with lots of hay or straw to play and rootle in, some soil for minerals, and goings on to watch, than they would be outside in deep, wet, cold mud. And yes, for 2 or 3 weaners in a large stable with plenty of straw, and access to some outside space - and some soil, however delivered - some of the time, it shouldn't be too much hard work. (Sows and piglets would be more work, but weaners aren't massive for a couple of months and then go off after a couple or three more!)
Feed is eye-wateringly expensive though, and feeding kitchen scraps mostly illegal, so check your plans / sums...