Male vs. female Belgian Malinois: what actually differs
This comes up constantly when choosing a puppy, and the honest answer is that individual temperament and line vary far more than sex does — but there are a few real, general tendencies worth knowing.
Size
Males are typically somewhat larger and more heavily built than females, generally by a few kilograms and a couple of centimetres at the shoulder, though there's plenty of overlap between a smaller male and a larger female.
Intensity and focus
Some working-line breeders and handlers describe males as slightly more likely to show overt intensity and handler focus, while females are sometimes described as a touch more independent or "thinking for themselves" — but this is a loose generalisation with wide individual variation, and plenty of exceptions exist in both directions. Line and individual breeding matter far more than sex for predicting actual working drive.
Hormonal behaviour if left intact
Intact males may show more roaming, marking and interest in intact females in season, and can be more prone to reactivity toward other intact males. Intact females go through heat cycles roughly twice a year, with associated behavioural and physical changes, and require careful management to avoid unwanted breeding. Most of these differences are substantially reduced by spaying or neutering, timed based on a vet's guidance around growth and health factors rather than a fixed default age.
Multi-dog households
Same-sex aggression can occur in either sex, and isn't reliably predicted by sex alone — individual temperament, introduction process and management matter more. Some experienced multi-dog households find opposite-sex pairings tend to have fewer conflicts, but this isn't a guarantee, and a poorly matched opposite-sex pair can still have serious conflict.
What actually matters more
Line, individual temperament, and how the puppy or adult dog is raised and trained have a far bigger impact on the dog you end up with than sex does. If you're choosing between two specific puppies, meeting them, seeing the parents, and asking the breeder about individual temperament will tell you more than any general rule about males versus females.