The Superhero Database Classification number, or SHDB Class, is a number that represents the overall 'power' of a character. All traits of a character are used for calculating the Classification.
What it DOESN'T mean
This doesn't mean that a higher class would always beat a lower class character. But the bigger the difference in Class is, the more obvious it is who'll win in a fight.
How is this calculated
( INT^1.3 + (STR*0.5 )^2 + (SPE*0.5)^2 + DUR^1.6 + (POW + (SPS*SPL))^2 + COM^1.8 ) ^ TIER
Super Power Score and Level
Every Super Power has a score (SPS) that is used to calculate the Class. Each Super Power also has 3 levels (SPL). The level is set when connecting that Super Power to a character. The level determines the final score, of the Super Power, being used in the calculation.
Strange Supreme has been absorbing the mystical powers of countless powerful beings for centuries, greatly amplifying his own powers. are there any indications that the Child from Young Justice has done anything like this? (No.)
Strange Supreme tore apart reality by interrupting an Absolute Point in Time and resurrecting Christine Palmer. did the Child from Young Justice demonstrated warping warping on this scale?. (No.)
Strange Supreme is the most powerful magic user, while the Child was not designated with a similar title only where to some extent showed high level magical ability
the result here that it's just that Strange Supreme takes it easy.