In a typical right-hand, right lead position, a stick or primary weapon would be in that front hand, a knife or backup weapon in the left, guarding closer to the body. The purpose of the longer lead weapon is to maintain distance and keep opponents at bay, while the purpose of the retracted secondary weapon is to punish anyone who gets inside that perimeter. As such, this is a more defensive posture (as in mindset, not a static pose).
A left lead, on the other hand, is more aggressive. That brings the shorter weapon into a more active countering range, where it and the lead hand have overlapping reach and the ability to coordinate and cover each other more effectively. The attitude there is “come in if you dare”, as an opponent will be facing both fangs at once, not as much sequentially. A savvy opponent will note such thing, but which can change in a split second. Footwork can fix many problems such as distance and angle, as well as hide intention and probe to set up an opponent.