They may be fine depending on the size of your tank.
I'd say a 20g Long at least. And Cory cats need to be in groups, preferably 6 or more is best. A pair of Bolivians should be ok. But livebearers, like Swordtails can be a pain when they start pumping out babies. But if you do 2 male Swordtails that might work. If you want females, Livebearers should have 3-4 females per male or the males pester the girls to death.
A bigger tank would make sure things stay peaceful. But I would not put Bolivians or Swords in anything smaller than a 20g. IMHO
FYI there are over 150 species of Corydoras Catfish. At least 3 dwarf species, but they do best with small tank mates. Corydoras aeneus or paleatus are both good beginner Corys.