It does matter in that different sequencers have different features available. If you were using a python script or had some weird controller that was using its own effects that would matter as well.
Not very good at sequencing but I tested a simple on effect in xLights and did one ramp up and then one ramp down. It looked good for breathing to me. Here is video that explains the on effect
https://www.youtube.com/watch?v=VygKUouKUHU
A Shockwave might give you the effect you are looking for. Here is a video on that:
https://www.youtube.com/watch?v=QWQ37CoI8js
On the prop I was testing, Fire looked good for breathing. It was irregular breathing but gave a nice up and down with subtle color change that reminded me of breathing.