There currently is no good way to change the speed of e.g. a slide transition. If you go to touchgfx\framework\include\touchgfx\transitions\SlideTransition.hpp, you can change the steps (and thus the speed speed) in the constructor. This would affect all transitions - But if you modify the generated files the change would get overwritten.
An animation has an easing-equation associated with it. The fewer steps, the faster the animation.
template <Direction templateDirection>
class SlideTransition : public Transition
{
public:
SlideTransition(const uint8_t transitionSteps = 20)
: Transition(),
snapshot(),
...
/Martin