Answered: Controlling multiple unseated cones

According to the definition of stacked:
a) Fully nested on a Goal (see Figures 5 & 6).
b) Fully nested on a Stacked Cone (see Figures 7 & 8).

If multiple cones are on an unested cone they are therefore not stacked.
now if a robot is to grab one of the cones and move them to be nested but in doing so are controlling the movement of multiple cones as ruled illegal in SG9:
Robots may not Possess more than one (1) Cone at a time.
Minor violations of this rule that do not affect the Match will result in a warning. Match Affecting
offenses will result in a Disqualification.
This may be match affecting as the cones are now scored after the cones are moved and therefore could be interpreted as a DQ.
My question is is this regarded as legal to nest multiple unested cones or is this illegal if intentionally done.

It is impossible to issue a blanket ruling based on a hypothetical action. The determination as to whether it was an <SG9> violation or not would depend on whether or not the Robot was truly Possessing the Cones (i.e. controlling their movement in the Robot).

Please see this similar question with a specific example of an action that would be considered legal: