Both of those handsome guys are males and once they feel settled in the aquarium will likely fight. Best keep males to separate tanks.
Females are plain silver, with the exception of female powder blues which tend to be a dull blue (yours is a very nice bright blue) without the red trim to the fins that yours has
This is a female dwarf. If you are in North America, females are extremely hard to find. Any with colour in the store will be males.