They both look like mixed breeds. The first one might have some White Rock in him, while the second one probably has some Barred Rock in him, but other than that, I don't know what breeds went into them.
Hatcheries sell Sex Link chickens, male and female. Sex Links are always crosses. The light colored rooster with buff/red barring is most likely a Red Sex Link rooster. They are a cross of either a Rhode Island Red or New Hampshire rooster with a Barred Rock hen.The black and white rooster with barring is probably a Black Sex Link rooster. They are a cross of a
Rhode Island Red Roo and a Barred Plymouth Rock Hen.