Scramble Power
From Transformers Wiki
Scramble Power (スクランブル パワー Sukuranburu Pawā) is a special ability possessed by several combiners which gives them the means to swap around the individual robots which make up their limbs. By doing so, they can create new configurations which better utilize the skills of the individual robots, thus significantly altering the outcome of battle or something.
The exact nature of Scramble Power is unclear. At first glance, it would seem to be a mechanical design, as some combiners are engineered with the ability to swap limbs while others are not. Scramble City: Mobilization However, it is sometimes presented as being less of a work of engineering and more of a technique or skill which is acquired through training. And other times, it appears to be more of an intangible, almost mystical power that can be transferred to and accessed even by those physically incapable of combining, such as Powerglide and the Minibots. Fight! Super Robot Lifeform Transformers #8