I've made assumptions on some parts here, I'll label them in italic.
I've had some calculations on Marisa's Master Spark, what width and what height it is.
Let's say Marisa's height is 130cm, because I saw the in-game character and pixels on some games look fairly short.
Let's say the play area is 600x800. (If we assume that the play area is 3:4 aspect ratio.)
Let's say the Master Spark covers roughly 85~90% if the play area.
Calculations:
Height of the Master Spark:
Minimum: 130cm * 0.85 = 110.5cm
Maximum: 130cm * 0.90 = 117cm
Width of the Master Spark:
Minimum: 110.5cm * (4/3) = 147.33cm
Maximum: 117cm * (4/3) = 156cm
So minimum height and the maximum height
is roughly 110.5 to 117cm, and the minimum and the maximum width is 147.33cm and 156cm.
This is only my hypothesis so feel free to do your own!