Basenjis are like potato chips, can't just have oneā¦
Male puppy to be sure is the safest way to go, opposites usually work the best. There will be lots and lots of snarking bring in a puppy, but that is usually the older one "explaining" what is or is not acceptable..... And trust me, you can never fully explain the noises they make... only when you hear it for yourself. Most people think they are trying to kill the pup... but they are not doing anything different then Mom Basenji or other adults in the house would do. If you are close to your breeder, best to introduce your girl at the breeders home, netural territory....
You will find when you get home the first few hours are all fun and games, then your adult will look at you and say "Seriously? Isn't it time to this one to go home?" And be sure to fuss over the adult, they were there first and should be treated that way.