User blog comment:Borumori/a question about quirk types/@comment-45358040-20200401062805

Keep in mind that this is only my personal opinion/understanding but I believe the key difference between Emitter and Tranformation Quirks is dependant on the actual effect of the Quirk. What I mean by that is regarding Emitter class Quirks the physical alterations the Quirk causes in its user are more of a visual expression of the Quirk rather than what the Quirk actually does. E.g. One For All causes All Might to bulk up when used but it's actual effect its to allow its user access to stockpiled power. Similarily Sugar Rush causes Rikido to bulk up when used but it's actual effect is to multiply his strength for every 10 grams of sugar he ingests.

While with Transfomation Quirks, the transformation of the body is, in essence is the effect of the Quirk.

Also regarding your question of needing to ingest something: "Accumulation-type Quirk's are powers that, in order to function properly, require the user accumulate something ahead of time, such as power, energy, mass, or a particular resource. Some such Quirks are One For All, Rewind and Fat Absorption."

One For All and Rewind are Emitter type Quirks while Fat Absorption is a Transformation type Quirk. So the Accumulation sub-type is not limited to just one class of Quirks.